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5>eparttTieitt /o/ /w^ ra of "3$ltne£v. 


(P. G. MORGAN, Director. I 

BULLETIN No. 14 (NEW Series). 

T M E G K ( ) T^ O G Y 









To ar^oTiipoitY BuHetin, 7P-'11 .Ni-wPlymtnith Subdiviaion .TarurtxtJU Divisiofv arui Zaii'l DUtrict, 

r A S M A 

TrigoneTnetricah Stations^ 

RaHwaya ,, 

Oil see/taj/es (roftorted) - ^ .,, 

1 . {risportnl, ) 

- Reference to Geolo g ical Colours and Si fcn^ 


ICIaystonea, sandsloncs.andconijlomeratea 
wpoaed at surface or very thinly cov 
-ered wilh volcanic debris 
II Eipoaed in vol'eys bul overlain by cor«id 
(\-eroble thicknets of volcanic debris 

r. 7^ QEH-grr.z .(- WhrirdsUf. Jiu,,- 1911. 

PouBkai Serum 

I InlBrmediato volcanic agylomei 

1 breccias, and tufTs 

Cbtilcinporaneous peaty beds.. 

Graveh. sands, and mude — 


Areas of local 

Outcrops of boulders of Pouakai Serie 
„ nner debris , 
with observed strike and dip -. 


To cu:<;oT/ipaiir BulLatiii N'-'M' . T^i-ty Plvriwiitli Subdii'ijf'on . TaiutuiAi Vivi-simi, uiid Laiul, District , 





(^ including a small portion of Pir-ongia Division ^ Auckland Land District) 
Scale of Miles 

l ^^a O ^ ^ ^ ^ 5 ^ , -^ 


Reads shown thLta ~ — gg===^ 

Triqonometr-ical StCLticne — „ »> - C ° iB'}/' 

EdqeeofBush „ _ _ „_ ?:^>»or>^ 

OWOTTip „ „ ~ -JL?5j^-* 

Oil yyells - prodviciriff „ „ _ • 

« „ drilling „ .. _ Q> 

n 1. 7T^ up orpart-\ 

■tally in position but not L „ _ O 

operattn^ or producing \ 

(?tZ. WeUs ■ abandoned, ., ,. _ 4 

OH seepages ., **- X 

- reported „ , , _ X 

Gas rents ,. .,— o 

„ „ - reported--^ ,. _ X 

Areas 'irt whiciv 1 „ „ (^ p^ • V 

comcaZ hills occur \ ^'--.T.^!' ^\ Tf^ S^ 



1\ HVlrt^ 

Edge of Tapuae - | 
'Manganui Hidge J 

— R eference to Geolo g ical Colours and Si fena — 

TRIAS -JURA Grauwackes and argillites . 

Gns/ro Series . 

iCIaystones. sandstones, and conglomerates] 
exposed at surface or very thinly cov- ■ 
-ered with volcanic debris. 1 

I Ejcpoaed in valleys but overlain by consid-l 
1 -erable thickness of volcanic debris. ' 

\ h}uakai Series . 


AND PLIOCENE I i '^*®'~'^^' volcanic agglomerates, 
[1 breccias, tuflTs. and flows. 


j Gravels, sands, and muds 

Outcrops with observed strike and dip X 

ChmpUed from. data. ohtcuneA from, the Larjis 
and Svjrvey Depamnent . 

Qeology ^ E.deC. Clarice and, frorrb riiaps Tr/ 
ettrller viwestignXors 

CampiUdanddrawnhyaEMiorrw^W.Bcz^dsZey July 1911. 


Bt Authorittf : John ftiaokay, Qooernmcnt Printer. 

To ft-f^ro7npa/iv -Bulletui^ 17'^ j^i .NcyvPlytnoxtth SubdJJi'LsiGri.TajcLfiaJu Divtsioiv art/i IJa/vU District'. 




- Scale of Chains 

— Reference to Geolo g ical Colourgand Si fens — 

( O/iairo Series 
Masses of claystone interbedded with r"ff" ~T~1 

volcanic debris of Pouakai 'Series I ^l 1^1 

IPouakar Serie s 

Intermediate volcanic agglomerates. I | 
breccias, tuffs and flows I I 

PLEISTOCENE 8. I ^ , , I 1 

RECENT Gravels, sands, and muds 

Areas of local subsidence }6<. 

Outcrops of boulders of Pouakai Series # 

_ finer debris - „ „ + 

„ with no observed strike and dip ■*■ 

Lava flows f 

Compiled, frarn, dcUa, obtcuunedi from/ 
^le Lan.ds <xnA Stjj-vey Deporfjrrvent, 
Qeology hy E.deC Clarke,. 

^ ^ l-l -t^ 

Roads shown thits 

Tri^onometrtcctl Stations „ j» - C ©lefl 

Ed^ee of Bush 



Oil Welts - proctucin-ff 
„ driUinff _ 

„ „ 7T^ t^ orpctrt 

■xaUty 171 posituirv, bitX not — 
operaiing or prodtuitng 

Oil Wells 'Ohoundoned, , 

OH seepages , 

.. " - -reported , 

Qas vents 

„ ,. ' reported, 

Compiltd anddrawnbyG flJJan-is arui, WSard^ley , June 1911 

Bf AuthoHts I Atka StaQUoj/. fhoemmuit Priater. 



^li. - .alofflon.lf, •wi. - ■ppwmlly. UJn. *^ 




Jpi"'""""" '■ 

Digitized by the Internet Archive 
in 2013 


Geological Survey Office, 

Wellington, Gth May, 1912. 


I have the honour to submit herewith Bulletin No. 14 (new 
series) of the Geological Surve}' Branch of the Mines Department. 
This Bulletin., which deals with the general and economic geology of 
the New Plymouth Oilfield, is the work of Mr. K. dc C. Clarke, M.A., 
now of Auckland University College. 

The field-work in connection with the preparation of this report 
was done by Mr. Clarke, under the direction of Dr. J. M. Bell. 

The Bulletin contains fifty-eight pages of letterpress, together 
with two general maps, a geological map, and a large sheet giving a 
^-^bulated comparison of boreholes. 

1 have the honour to be, 
Your obedient servant, 


Director, New Zealand Geological Siuvev. 

Hon. James Coivin, 

Minister of Mines, Wellington. 


Letter of Transmittal 


Chapter I. — General. 


Introduction . . . . 1 

The New Plymouth Subdivision, and Econo- 
mic Reasons for Geological Work therein. . 2 
Conduct and Character of Work . . . . 2 

Acknowledgments . . . . 3 

Industries . . . . . . 3 

Climate . . . . 3 

Scenery . . . . . . 3 

Towns, and Means of Communication . . 4 

Population and Early History 4 

Physiography . . . . . . . . 4 

introduction . . . . . . 4 

The Land . . 5 
(L) General Relief .5 

(2.) Higher Land . . 5 
(a.) The Tapuae-Manj^anui Ridge 

and Terraces thereon . . 5 

Physiography — continued. 
The Land — continued. 

(2.) Higher Land — continued, 
(b.) Conical HiUs 
(c.) Sugar-loaves 
(3.) Low-lying Country 
[a.) Coastal 
(6.) Inland 
(c.) River-flats 
Ponds and Swamps 

Explanation of some of the Physiographic 


Chapter II. — General Geology. 

Outline of Geology . . . . . . 12 

General Sequence of Formations. . . . 12 

General Account of the Structure of the 

Formations . . . . . . 12 

Geological History . . . . 13 

Comparison of Classification of Rocks with 

those of Previou.s Investigator.s 13 

The Onairo Series . . . . 15 

Introductory . . . . . . 15 

General Distribution . . 15 

Petrology . . 16 

( 1 . ) Claystones and Sandstones 16 

(2.) Conglomerates ..17 

Structure ..17 

Interrelationship of the Diflferent Members 

of the Series . . 18 

Palseontology , . 19 

Age and Correlation .21 


The Pouakai Series . . 21 

Introductory . . . . 21 

General Distribution . . 21 

Structure and Interrelationship of the 

Different Members of the Series . . 21 

Petrology . . 22 

(1.) Igneous Rocks ..22 

(2.) Claystone Masseti, Quartz Pebbles, 

&c. . . .24 

(3.) Lignitic Beds .24 

Mode of Origin . . 24 

Ago and Correlation . . 25 

Pleistocene and Recent Rocks . . 26 

Introductory . . . . 26 

Alluvial and Swamp Deposits . . 26 

Marine and Flu vio- marine Deposits . . 27 

ifColian Deposit.s . . . . 28 

Chapter III. — Economic Geolooy. 

Introductory . . 29 

Petroleum . . 29 

Present Position of the Petroleum Industry 

in Taranaki . . 29 

History of the Petroleum Industry in Tara- 
naki . ". .30 
(1.) Introductory .30 
(2.) First Period of Activity : 1865-68 . . 30 
(3.) Second Period of Activity : 1889 to 

the Present Day .31 

(a.) 1889-1904 .". .31 

(6.) 1904 to the Present Day 33 

(i.) The Moturoa and Taranaki 

Petroleum Companies 33 
(ii.) The Inglewood Oil-boring 
and Prospecting Com- 
pany (Limited) . . 35 
(iii.) The Moa Petroleum (Li- 
mited) . . . . 36 
(iv. ) The New Zealand Standard 

Oil Company (Limited) 36 
ii — New Plymouth. 


Petroleum — continued. 

History of the Petroleum Industry in Tara- 
naki — continued. 
(3.) Second Period of Activity — continued. 
(6.) 1!)04 to the Present Day — continued. 
(v.) The Taranaki Oil and Free- 
hold Company (Li- 
mited) . . 36 
(vi.) The Bonithon Freehold 
Petroleum Company 
(Limited) . . 36 
(vii.) The New Plymouth Petro- 
leum Company (Li- 
mited) . . 37 
(4.) Comments on Prospecting Methods. . 37 
Theories regarding the Origin and Mode of 

Accumulation of Petroleum . . 37 

(1.) Origin .37 

(2.) Mode of Accumulation . . 38 


Chapiek hi. — Economic Geolooy — continrued . 

Petroleum — continued. 

Evidence as to the Existence of Payable 
Oil-reservoirs in or near the Subdivi- 
sion . . . . . . . . 38 

(1.) Recapitulation of Geological Struc- 
ture of the Subdivision . . . . 38 

(2.) Oil-seepages . . . . . . 39 

(3.) Analyses of Oil . . . . . . 40 

(4.) Escapes of Natural Gas . . . . 43 

(5.) Analyses of Gas . . . . . . 46 

(6.) Conclusions . . . . . . 46 

(7.) Recommendations regarding Future 

Prospecting for Oil in Taranaki . . 47 


Iron-ores . . 48 

(I.) Ironsand . . . . 48 

(1.) Introductory .48 

(2.) Composition of Ironsand . . 48 

(3.) History of Attempts to treat the 

Ironsand . . . . . . 49 

(4.) Method and Results of Smith's 

Patent Smelting Process . . 50 
(5.) Remarks on the Economic Pos- 
sibilities of the Ironsand . . 51 
(II.) Limonite.. .. .. ..52 

Materials for Roadmaking . . . . 52 

Building and Pottery Materials . . . . 52 

Appendix . . 

Tabular Comparison of Records of Bores 


.. 53 

In portfolio. 


1. Map of New Zealand showing Land Districts and Divisions 

2. Map of Taranaki Division showing Survey Districts and Area geologically 

3. Geological Map of Waitara Survey District . . 

4. Geological Map of Paritutu Survey District . . 

5. Geological Sketch-map of Portion of Taranaki Division 


Facing page 
. . vi 
. . vi 

\ ^" 
I portfolio. 

AOOO.'t- 03.318 

By Authority : John hdackay^ Government Prtnter, 





TAR A N A KI P L V I S I () N . 



Tho Isow Plymouth Subdivision, and 
Economic B«3asons for Geological Work 
Conduct and Character of Work 

Towns, and Means of Communication 
Population and Early History.. 
The Land— 
(1.) General Rjlief 
(2.) Higher Land— 

(a.) Tho Tapuac-Manganui Ridgo 
and the Turraces thereon 


Physiosraphy — continued. 
The Lind — continued. 

(2.) Higher Land — continued. 
(6.) Conical Hilb 
(c.) Sugar-loaves 
(3.) liow-lying Country— 
(a.) Coastal . . 
(6.) Inland .. 
(c.) River-flats 
Drainage-channels . . 
Ponds and Swamps 

Explanation of some of tho Physio 
graj)hic Features 
Literi' nr,' 



The Taranaki Division, with a portion of which the present report deals, lies on the west 
coast of the North Island between latitudes 38° 24' S. and 39° 47' S., and longitudes 
173° 47' E. and 175° 29' E., thus coinciding in extent wth the Taranaki Land District. 
It is bounded on the west and south-west by the Tasman Sea, and on the north by the 
Mokau River to its source. From this point the eastern boundary crosses to the watershed 
of the Ongaruhe River, which it follows to Taumarunui, whence the Wanganui River is 
followed almost to Pipiriki. The south-eastern boundary is formed by a straight line 
running in a south-westerly direction from near Pipiriki to the mouth of the Patea River. 

With the exception of Mount Egmont and the subsidiar\' ranges in its neighbourhood, 
the Taranaki Division presents comparatively few features of interest from a scenic 
or geologic standpoint. The division, wherever settled, is almost entirely an agricultural 
and pastoral district, and at the present day is chiefly noted for its large output of 
butter. With the exception of mining for coal on the Mokau River, and of a moderate 
1 — New Plymouth. 

amount of excavation for brickmaking and roafl-maradamizin<r. attempts to develop the 
mineral resources of the division have been confined to boring for petroleum, mainly 
in the immediate neighbourhood of New Plymouth ; prospecting for gold and other 
metals in the Kaitaki or Patua Range ; and to various attempts to smelt on com- 
mercially payable lines the ironsand whicli is found along the sea-beaches. 

The New Pi-vmouth Subdivision, and Economic Reasons for Geological Work 


The New Plymouth Subdivision, comprising the survey districts of Paritutu and 
Waitara, covers an area of approximately 218-2 square miles. It is boimded on the 
north by the shore of the North Taranaki Bight from the mouth of the Waiwere 
Stream, about three miles south-west of the New Plymouth Breakwater, to a point a 
mile and a quarter north of the mouth of the Mimi River, and thence by a straight 
line running due east for about half a mile. Of the remaining boundaries, the eastern 
and western are Unes running south from the ends of the northern botmdary as defined 
above, and the southern is a straight Une rmining east and west through Huirangi 
Trigonometrical Station, which is about lOJ miles due south of the mouth of the 
Waitara River. 

Near New Plymouth a large amomit of money has been spent during the last 
forty years in attempts to obtain, by boring, a payable supply of mineral oil, the existence 
of which in small quantities has been recognized since the earhest days of European 
settlement. Although there is no desire on the part of the writer to detract from 
the enterprise and pubUc spirit which have often been marked characteristics of the 
various Taranaki petroleum ventures, it has to be admitted that transport facihties, 
ownership of properties, and other fortuitous circumstances have usually been the 
determining factors in the choice of bore-sites, and that Uttle or no attempt has been 
made to unravel the geological structure of the comitry and to arrive at general con- 
clusions as to the probable distribution of the|petroleum. 

The investigations detailed in this report were undertaken with the object of supplying 
such geological knowledge as would enable further oil-prospecting to be carried on in an 
intelUgent and systematic fashion. With this purpose in A-iew investigation was not strictly 
confined to the New Plymouth Subdivision, but was extended beyond it, as far as time 
would allow, whenever it seemed that by so doing further knowledge of the area mider 
review would be gained. 

Conduct and Character of Work. 

The field-work detailed in this report was carried out in the two periods, November, 
1909, to February, 1910, and November, 1910, to January, 1911. During the greater part 
of this time the writer had the assistance of Mr. R. W. Davies, of New Plymouth, whose 
intimate knowledge of the comitrj- was of very great value. All the information available 
at the Lands and Survey Office, New Plymouth, was plotted by the draughtsmen of the 
Geological Survey upon large sheets on a scale of 20 chains to the inch. Owang to 
the great amount of detailed work available from the Lands and Survey Office, it was found 
mmecessary to carry out any supplementary surveys — outcrops and other features being 
fixed with sufficient accuracy from the available data. 

All ridges, streams, roads, and other features which seemed hkely to afford information 
as to geological structure were examined, more especially in the eastern portion of the 
subdivision. In the western part of the area under review such close scrutiny was found to 
be unnecessary, nor was it possible in the more hurried reconnaissances made outside the 


The writer received much Idndly assistance on all sides in Taranaki. The directors 
and employees of the Taranaki Petroleum Company and the New Zealand Standard 
Oil Company were ever ready to give all information in their power. To Mrs. G. C. 
Fair, and Messrs. D. Berry, F. P. Corkill, Foote, Murdoch Fraser, T. Furlong, T. li. Harle, 
R. C. Hughes. T. Nicholls, 0. Samuel, Saxton, S. Percy Smith, T. P. Smith, Edward 
Trythall, and A. E. Watkins the writer wishes to tender his thanks for much assistance 
in a variety* of ways. Mr. Frank Simpson (Chief Surveyor), Mr. W. H. Skinner (Chief 
Draughtsman), and other oili. ers of the Lands and Survey Office in New Plymouth, 
promptly and courteously responded to all I'equests for topographical and other informa- 
tion. Unless otherwise stated, the analyses contained in this report were made by the 
Dominion Analvst, Dr. J. S. Maclaurin, and liis staff. 


The staple industry of the New Plymouth Subdivision is dairying. Almost all 
the available land of the subdivision has been cleared of the dense bush which at 
one time covered it, and has been subdivided into small farms. The amount of butter 
exported from Taranald Proxnuce during 1907 was estimated at 5,693 tons, and that of 
cheese at 6,630 tons. 

Large freezing-works, which during 1908 produced 6,220 tons of frozen meat, are 
in active operation at Waitara. 


The climate of the area under considc^ration is warm, moist, and equable. As 
would be expected from its geographical position, the prevalent westerly winds usually 
bring rain, whereas the southerly and easterly winds are dry. The average monthly 
rainfall at New Plymouth, compiled from records extending over thirteen years, is as 
follows : 



Mnr. I April. 

.\viragf moiitlily . 4()7(i 4-322 5050 i 4-890 
i-aiafall in inches. 



Jniw. July. Aug. Sept. Oct. Nov. Dec. 

6-4061 5-673 4-902' 3-326 0-003 4-812 4-394 

It should be noted that the rainfall in the southern part of the subdivision, towards 
Fnglewood, is constantly liigher than that near New Plymouth. Extremes of heat 
and cold are practically unknown. The following table shows the average monthly 
temperatures <at New Plymouth, compiled from records extended over a period of 
twenty-five years : — 





May. June. July, i Aug. 



Nov. Dec. 

Average monthly 
tempt'r<itui-e i n 
(Icproi-.s Fahr. 





55-57] 52- 19 









Within the subdivision itself the scenery is of the mild and pastoral order, enhanced 
by views of the open ocean. The magnificent volcanic cone of Egmont (8,260 ft.) 
to the south-west imparts, however, a certain distinctiveness to Taranaki scenery, and 
1* — New Plymouth. 

saves it from any accusation of dullness or monotony. The coastal scenery is of a low, even 
cliaracter, varied just beyond the northern boundary by the imposing heights of the 
White CUfTs, and near New Plymouth by the rocky prominence which forms Paiitutu, 
and the small skerries of a similar description known as the Sugar-loaves. 

Towns, and Means of Communication. 

The subdivision contains two towns of some size — New Plymouth and Waitara. 
The former is well situated on rising ground bordering the Tasman Sea, and forms the 
terminus of the railway to WelUngton. New Plymouth owes its predominance over Waitara 
to prior settlement, and to the possession of a breakwater, whxh converts the open road- 
stead into a harbour, accessible in almost any weather to steamers not exceeding 400 ft. 
in length and 21 it. in draught. The harbour improvements at present in active progress 
are expected, in two years' time, to allow of the berthing of vessels drawing as much 
as 28 ft. 

The town of Waitara, though less advantageously situated from a scenic point of view, 
possesses a natural advantage in having the mouth of the Waitara River as the nucleus 
of a harbour. The town is also more central for receiving the greater part of the 
inland trade. Owing to the bar at the mouth of the river, the port of Waitara 
is open only to the smaller coastal steamers, which maintain a considerable trade with 
neighbouring ports. The large steamers, which load produce for export trade, have at 
present to be tendered both at Waitara and New Plymouth. 

On land there is direct railway communication between New Plymouth, Waitara, 
and Welhngton. 

Numerous roads traverse the country in every direction, and these are, with very 
few exceptions, in an excellent state of repair. Post-offices and telegraph or telephone 
stations are widely distributed. 

Population and Early History. 

The population of the New Plymouth Subdivision, as judged from the census 
returns of 1911, is approximately 12,717, of which 5,240 persons are residents of New 
Plymouth (or 7,499 including the suburban area), and 1,452 of Waitara Borough.* 

Taranaki was first settled by Europeans about the year 1840, when ships chartered 
by the New Zealand Land Company brought a number of emigrants, who were chiefly 
from Devonshire. No account of the vicissitudes of this settlement can here be given. 
The well-known Taranaki wars, which are fully recorded in various publications, have 
left many interesting landmarks in different parts of the subdivision. 



At first glance the physiography of the district under review appears simple. 
Further examination seems, however, to disclose some anomalies which cannot be 
easily accounted for. The area may be described as a portion of an extensive plain of 
comparatively recent and intermittent elevation above sea-level. The sculpturing of this 
plain, now considerably advanced, varies markedly with the character of the imderlying 
strata. The drainage-system of the whole area has been notably affected by the 
building-up of the volcanic cone of Egmont. 

Advance estimates of population were kindly supplied by the Government Statistician's OflSce. 


(1.) General Rdief. 
Tlie land-surface of the New Plymoutli Subdivision may be described in general 
as a deeply trenched plain showing no marked elevations, but exhibiting a distinct 
belt of higher country, which separates a zone of low country- on the sea side from 
another area of low elevation on the inland (southern) side. 

(2.) Higher Land. 

(a.) The Ta-puae-Manganui Ridge and Terraces thereon. — This ridge of liigher land has 
a coastal width of about five miles and a half, extending from the town of New 
Plymouth to the mouth of the Tapuae Creek. From the sea-coast it may be traced in an 
easterly direction as far as the junction of the Manganui and Waitara rivers. From the 
eastern margin of the Manganui Valley the seaward edge of the ridge runs in an east- 
north-east direction, reaching the sea-coast at Pukearuhe, about two miles and a half north- 
east of the boundary of the subdivision. West of the interruption by the Manganui 
River the ridge is composed, so far as is known, almost entirely of volcanic debris of 
the Pouakai Series,* of Upper Miocene or later age. There is reason to suppose that, 
at some points at least, Miocene sedimentaries of the Onairo Series he at no great 
depth below the surface. The inland margin of this portion of the ridge lies in most 
places near the southern boundary of the subdivision. East of the Manganui Valley 
the ridge abuts against higher land (rising to an average height of nearly 1,000 ft.) 
formed of the Miocene sedimentaries of the Onairo Series. East of the Manganui, 
therefore, the ridge really loses its ridge-Uke character altogether, and forms what may 
be generally defined as a terrace fronting the older rocks. The seaward margin of the 
ridge is difficult of exact definition, rising as it docs from the lower coastal land in a 
series of terraces, of which four can generally be recognized. These terraces have been 
much dissected by the numerous streams. 

(6.) Conical Hills. — In the neighbourhood of Lcpperton, bordering on the seaward 
margin of the Tapuae-Manganui Ridge, and again just outside the south-east corner of 
the Partitutu Survey District, near Inglewood. occur assemblages of small conical hills, 
which it seems most reasonable to regard as the denuded remains of one or more volcanic 
cones. The Lepperton hills are scat'ered over an area of about nine square miles, and 
those near Ingle >\ood over an area exceeding seven square miles. Furl her details regarding 
these hills will be found in Chapter II. 

(c.) Sugar-loaves. — On the coast-hne about three miles from New Plymouth the uniform 
character of the topography is strikingly interrupted by the occurrence of a group of 
exceedingly steep-sided pyramidal rocks. Of these, Paritutu and Mikotahi are on the 
mainland. Paritutu, the loftiest of the group, which rises precipitously from the sea- 
margin to a height of 505 ft., is bordered on the landward side by sand-dunes covered 
with vegetation. The rest of the rocks are islands of heights varjnng from a few 
feet to 268 ft., in the case of Moturoa, which, excepting Paritutu, is the most conspicuous 
of the Sugar-loaves. Outlying reefs doubtless mark the sites of similar prominences 
worn away by the action of the sea. With the exception of Mikotahi, the Sugar-loaves 
are composed of sohd lava. 

(3.) Low-lying Country, 
(a.) Coastal. — The low-lying coastal belt has a maximum width of abo;,t six miles in a 
direction due south of Waitara, gradual y narrowing to the cast and west so that at the 
White Cliffi and near New Plymouth it is absent altogether. As may be seen from the 

* For an outline of the geolog}' of the subdivision, with descriptions of the scries mentioned in this ».<ction, 
Chapter II. 


general map, this low-lying land is continued beyond the \Vhite Chffs at least U) Awakino, 
in the form of a terrace never much more than a mile wide fronting the higher coimtry of 
Miocene rocks. There is little doubt that the low-lying coastal plain formerly extended 
far to the north and west of the present coast-line of the subdivision. Through this plain 
flowed the lower portions (now engulfed by the sea) of the Mokau, Mohakatino, and other 
rivers. Marine denudation has now advanced so far that but a narrov>- strip of the plain 
is left along the coast-hne north of the White Chffs. 

The greater part of the coastal plain is similar in surface-conformation to the 
Tapuae-Mangamii Ridge. It has a fairly uniform maximum elevation of about 200 ft., and 
is trenched and terraced by the nmnerous streams, which flow in a general northerly 

Immediately bordering on the sea the coastal lowland shows some development of 
sand-dunes. These are specially marked between the mouths of the Waitara and Henui 
rivers, where they attain a maximum \vidth of nearly one mile near the mouth of the 
Mangaoraka Eiver. Between the Breakwater at New Plymouth, where the sand-belt lies 
behind the upstanding Sugar-loaf of Paritutu, and the western boimdary of the subdi\'ision, 
the strip of sand does not usually exceed a few chains in width. The greatest heiuht 
reached by the sand-dimes is about 100 ft.* 

(6.) Inland. — The low-h-ing inland country south of the Tapuae-Manganui Ridge lies 
in great part beyond the southern boimdar\" of the New Plymouth Subdi\asion. It will 
therefore be sufficient to note here that it is generally an opeji plain, through which 
flow in shallow beds the numerous streams that drain the slopes of Mount Egmont. 

(c.) River-flats. — Flood-plains border the courses of all the streams in the subdivision 
almost to their headwaters, but none are of any great lateral extent. The most con- 
siderable flood-plain is that of the Waitara River, between Huiraugi and the sea. 


With the notable exception of the Waitara River, the streams and rivers of the New 
Plymouth Subdi\ision flow in a general northerly direction. Nearly all the streams pursue 
independent courses to the sea, the marked absence of tributaries being due to the 
comparative youth of the topography. In those parts of the coast where chffs exist 
the smallest streams often enter the sea by means of waterfalls, but all except these 
flow through narrow flood-plains and enter the sea at grade. There is a marked 
distinction between the streams draining the western and north-central portion of the 
subdi\nsion and those which occur in the south-eastern corner. The fornier follow an 
almost straight course through the volcanic debris of the Pouakai Series, varied by a 
small amount of meandering. In the south-eastern comer of the subdivision the water- 
courses follow more circuitous routes, and have cut out for themselves steep-sided gorges 
in the soft Miocene claystones and sandstones of the Onairo Series. In both classes 
of streams few, if any, waterfalls are to be found even near their headwaters. 


No sheets of fresh water worthy of the name of lakes are found Avithin the New 
Plymouth Subdi\-ision. A few small ponds exist, which may be classified as (a) those 
occurring in sand-diuie areas, (b) those which possibly owe their origin to local subsidence. 

(a.) The only case of a pond formed by the damming-up of streams by drifting sand 
is the small lagoon occurring in the sandliills about one mile and a quarter south-west 
of Paritutu. 

* For general information concerning New Zealand dune areas the reader may consult the comprehen- 
sive " Report on the Dune-areas of New Zealand" (C.-13, 1911), by L. Coekaj-ne. This report gives the 
area of the dunes between New Plvmoulb and the ilokau River as ll,t)21 acres, but this is apparently a 
misprint for 1,621 acres. 

(6.) There are at present two examples of ponds occupying possible areas of sub- 
sidence — namely, the Rotokare or Ratapihipihi Lagoon, about two miles south of New 
Plymouth, and the pond situated close to the Richmond Road, about three-quarters 
of a mile from the southern boundary of the subdivision. As will bo explained in 
Chapter II, there are a number of small basins within the subdivision which 
apparently owe their existence to local downfaulting, probably due to the removal of 
soluble matter from the underhnng strata. It seems hkely that the ponds mentioned 
above have originated in this way. 


Small springs at the junction of strata of different permeability are common throughout 
the subdivision. They are particularly abundant in the rocks of the Onairo and Pouakai 
Series (for descriptions of rocks see Chapter II), but occur also in the later accunm- 
lations, as, for example, along the contact of the wind-blown sands with more consoUdatcd 
debris. In this latter case the springs deposit considerable quantities of iron-oxide, 
which is also precipitated in less amoimt from water draining out of Pouakai rocks. 
Springs issuing from the Onairo rocks are not, as a rule, in any way remarkable. At 
German Hill, however, to the south of the subdivision — where Onairo rocks are possibly 
close to the surface (see p. 1(5) — a considerable precipitation of calcareous sinter has 
taken place from the water of a number of small springs. Water from one of these 
springs pelded the following analysis (results expressed in parts per 100,000) : — 

Sodium-chloride .. .. .. .. .. 1018 

Potassium -chloride . . . . . . . . . . 5-54 

Sodium-sulphat« 1817 

Magnesium-bicarbonate . . 54-44 

Calcium-bicarbonate . . . . . . 73-93 

Iodides . . . . . . . . . . . . Nil 


Sulphuretted hydrogen . . . . 0-30 

Remarks on tht; water i.ssuin<i from two of the petroleum-wells near New Plymouth 
will be found in Chapter III. 


The coast-line of the New Plymouth Subdivision exhibits no indentations except 
the mouths of the larger streams in the eastern pctrtion, which are tidal for a short 
distance. From the westeni boundary of the subdivision to the Sugar-loaves the coast- 
line is occupied by low sand-dunes, which again occupy the sea-frontage from the 
mouth of the Henui to the mouth of the Waitara. At Moturoa the coast-line is 
broken by the Sugar-loaves, and between Waitara and the eastern boundary of the 
subdivision, save where indented by the mouths of the larger streams, is fronted by 
vertical cliffs seldom more than 1(X) ft. in height. These cliffs are formed of Miocene 
sedimentaries capped by pyrodastic rocks. 

The sea is rapidly encroaching on the last-described portion of the coast-line. 
Abundant evidence of this is furnished by the rapid destruction of the sites of nume- 
rous old Maori pas or forlitied villages, which, within the memorj' of many persons, have 
dwindled to a mere vestige of their former size. 

The coast-line of the New Plymouth Subdivision therefore exhibits all the cha- 
racteristics of an area which has imdergone recent elevation. A still more recent slight 
depression is CNndenced by the sunken mouths of the streams in the eastern part of the 
subdivision. No evidence of such depression, however, is forthcoming in the western 
part of the area. 


A glance at the general map shows very clearly tliat the accumulation of the 
volcanic matter which forms Mount Egmont and the Pouakai Range has exercised a 
marked influence on the drainage-system of the area. As a result of the building-up 
of the great volcanic cone of Egmont, many small streams, draining its sides and 
radiating outwards from its summit, have originated. On the western, northern, and 
southern sides of the mountain these streams follow an almost straight course to 
the sea. The watercourses draining the eastern slopes of the moimtain are generally 
tributary to streams which were in existence before Mount Egmont. Below their junction 
Buch streams turn sharply to north or south and flow towards the sea. The most striking 
example of this is the Manganui River, which flows in a general easterly direction from the 
moimtain to its junction with the Waitara River, which thence follows a northerly course 
to the sea. 

There is little doubt that the extravasation of the great amount ol volcanic material 
which forms Mount Egmont and the Pouakai Range, together with the institution of so 
manv rapidly flownng streams bearing abundant loads of sediment, exercised a marked 
influence in the deflection of the slowly flowing muddy streams that drained the country 
to the east. This influence is clearly seen in the case of the Waitara and Wanganui rivers, 
and was also probably operative on the Mokau River, which in the lower part of its course 
exhibits a decided turning from a south-westerly to a westerly direction— a tendency which 
may have been more marked in earlier times before the removal by marine denudation 
of the greater part of the low coastal plain, and the consequent shortening of the course of 
the river. 

The writer is imable to propoimd a satisfactory explanation of the Tapuae -Manganui 
Ridge — i.e., of the portion hang between the mouth of the Tapuae Creek and the Manganui 
River. For convenience the term has sometimes been used more generally to include 
also the north-eastern extension of this ridge (see above, p. 5). The view that the 
low-lying country to the south of this ridge represents the former bed of a westerly- 
flowang river (most probably the Waitara), which was subsequently diverted, as described 
above, by the products of the Mount Egmont volcano, is favoured by the following consider- 
ations : (a) the existence of marked terraces, which from their inclination towards the sea 
would appear to have been formed by a river, at the foot of the Kaitaki or Patua Range on 
the southern border of this low country ; {b) the frequent occurrence in the volcanic debris, 
found at the seaward tennination of the low comitry, of water-woni pebbles of quartzite, 
grauwacke, argilUte, &c., which would seem to have been conveyed thither by a river long 
enough to reach back to the beds of conglomerate occurring abundantly in the Miocene 
rocks east of the subdivision. 

The low-hnng comitry to the north of the Tapuae-Manganui Ridge might similarly be 
ascribed to the erosive action of the Mokau River. In this case the ridge would be a 
residual of erosion. An insuperable objection to this view, however, is the behaviour of the 
numerous streams which were formed subsequently to the appearance of Mount Egmont. 
These streams, after crossing the southern lowlands, cut straight through the ridge on their 
way to the sea. 

A theory which ofiers an easy but imsatisfactory way out of the difficulty is that 
the ridge marks the scarp of a fault by which the coimtry to the south has been 
thrown down, and that the faulting took place with sufficient slowness to allow the streams 
to keep pace with it in their downcutting. Such a theory as this applied to a district of 
heavy rainfall and rapid denudation, in the absence of any structural data, must be \aewed 
with distrust. 


Tlie following list includes, so far as the writer is aware, all the publications of import- 
ance bearing on the geology of the New Plymouth Subdivision or its neighbourhood. The 
following abbre\'iations are eraploj'ed : Rep. G.S. — " Reports of the Geological Survey of 
New Zealand " ; Trans.—" Transactions and Proceedings of the New Zealand Institute " ; 
Q.J.G.S. — " Quarterly Journal of the Geological Society." A capital letter followed by a 
figure- thus, C.-3 — refers to a New Zealand parhamentarj^ paper. 

1843. Dieffenbach, E. : " Travels in New Zealand." Chapters vii and viii, vol. i, contain 
an account of geological and other features of Taranald. 

1850. Mantell, G. A. : " Notice of the Dinomis," &c. Q.J.G.S., vol. ^^, p. 319. " Infusorial 
Earth of Taranaki." Ibid., p. 332. Identities a number of diatoms from near 
New Plymouth. 

1866. New Zealand Gazette, 29th June : Sketch of Geology of the District. Probable that 
some surface indications of oil are due to decomposition of superficial lignitic lodes. 
Volcanic deposits were accumulated under the sea, and are at least 2,000 ft. 
thick, conformably miderlain by 2,000 ft. or more of sedimentary strata which 
overlie the brown-coal formation which is the ultimate source of the oil. Brown- 
coal formation extends under Mount Egmont in patches deposited in hollows in the 
Palaeozoic rocks. Since oil originates in Tertiary strata, the district shows some 
resemblance to petroleum-wells of Italy, the Crimea, and Asia Minor. From 
analogy with these fields, the author (? Hector) considers the proper place to 
prospect for petroleum is towards the Mokau River. Boring near Moturoa will 
never give large supplies of oil. Oil contains too large a proportion of carbon to 
render it altogether suitable for illuminating purposes. However, lighter oils 
may be obtained by boring elsewhere, as has occurred in other parts of the 
world. Quotes analyses of the oil, which will be found in Chapter III of this 

1868. Hector, James : " Taranaki District." Rep. G.S. during 1866-67, p. 2. Distinguishes 
a number of distinct formations between Mokau and New Plymouth. Emphasizes 
the absence of the alternate beds of sand and clay, which are found in the chief oil 
districts of the world. 

1874. Skey, W. : " On the Mineral Oils of New Zealand." Trans., vol. vi, p. 252. Gives 
results of examination of oil " from the Sugar-loaves," which is quoted elsewhere. 

1879. Skey, W. : " Preliminary Note on the Presence of One or More Hydrocarbons of 
the Benzol Series in the American Petroleum, also in our Petroleums." Trans., 
vol. xi, p. 469. Finds that in Taranaki crude ])otroleum the benzol series is 
well represented quantitatively. 

1879. Hector, James : " Progress Report." Rep. G.S. during 1878-79, p. 20. Brief 
accomat of geology of the basin of the Mokau River and of the north-eastern 
portion of the New Plymouth Subdivision. 

1887. Park, James : "On the Geology of the Western Part of WelUngton Provincial 
District and Part of Taranaki." Rep. G.S. during 1886-87, p. 24. On page 42 
short account of the geology of the district between New PljTnouth and Waitara. 

1887. Park, James : " On the Upper Wanganui and King-countrj'." Rep. G.S. during 
1887-88, p. 167. Deals mainly with coimtry to east of the subdivision, but on 
page 179 is brief mention of the topography of the Waitara district. 


1888. McKay. A. : " On the Discovery of Metalliferous Kocks in the Patua (Kaitald) 

Range, New Plymouth." Rep. G.S. during 1887-88, p. 35. Concludes that the 
deposits are moat probably surface sinters. None of the samples yielded more 
than a trace of silver. One contained 642 per cent, of copper. 

1889. Hutton, F. W. : " The Eruptive Rocks of New Zealand." Journal and Proceedings 

of Royal Society of N.S.W., vol. xxiii, p. 102. Contains a description of various 
igneous rocks from the subdivision and its neighbourhood. Further reference to 
this paper is made in Chapter 11, p. 22. 

1896. The Iron and Coal Trades Revieu, 10th July, 1896 : " The Ironmaking Resources 

of Australasia — 1, Now Zealand." Deals largely mth the Taranaki iionsand ; 
gives an account of attempts to smelt the ore, and considers that the deposits 
present great economic possibilities. 

1897. Elecirician, 17th September, 1897 : " The Magnetic Properties of Annealed Wrought 

Iron manufactured from the Ironsands of New Zealand." The results show that 
the wrought iron prepared from Taranaki ironsand by Mr. E. M. Smith's patent 
process is normal in its magnetic qualities under high and low magnetizing 

1898. McKay, A. : " Petroleum (Report of Government Greologist on the Present Condition 

of and Future Boring for) at New Plymouth." C.-9a. Describes the state of the 
New Plymouth Company's (Samuel's syndicate) workings, which at the time had 
proceeded as far as No. 6 bore. Concludes that there are oil horizons at 900 ft. 
and 2,000ft. approximately; that a further 1,000ft. might be bored without 
reaching carbonaceous beds likely to, or capable of, affording the oil stored at 
higher levels. 

1898. Hutton, F. W. : " Corrections in the Names of some New Zealand Rocks." Trans., 

vol. xxxi, p. 484. Reference to this paper is made in Chapter II. 

1899. McKay, A. : " Report on Petroletim at New Plymouth, Taranaki." C.~9, p. 3. 

Gives a history of the search for oil in the district, and extracts from reports on 
the prospects of the district. Considers that boring operations have proved exist- 
ence of oil at a depth sufficiently great to preclude the possibility of its derivation 
from superficial carbonaceous remains. But whether the oil-bearing strata are a 
continuation of the Mokau coal-beds is impossible of proof, since these would be 
5,000 ft. below the surface and beyond the reach of boring. 

1899. C.-9, p. 138. Abstract of McKay's Report (C.-9, p. 3). 

1899. C- 2, p. 13. Reference to successful tests of Taranaki ironsands. 

1906. Supplement to Taranaki Herald of 19th May : " Petroleum in Taranaki." An 

account of the earlier attempts to obtain oil in tlie district. 

1907. Maclauriu, J. S. : " Fortieth Annual Report of the Colonial Laboratory," p. 34. 

Analysis of crude oil from New Ph'mouth. The sample is shown to resemble 
Russian rather than American oil. 

1907. Hill, H. : " Oil-wells and Oil Prospects along the East Coast." Trans., vol. xxxix 

(1906), p. 509. Mainly deals with Poverty Bay oil, but also contains some reference 
to Taranaki. 

1908. Marshall, P. : " Distribution of the Igneous Rocks of New Zealand." Rep. Aust. 

Ass. Adv. Sci., vol. xi, p. 375. 


1909. B«-ll. J. M. : " Prelinntiarv Report on tlio Taranalci Oilfield." C.-14. Contains a 

brief account of the general features, geology, oil-bonng operations, and oil and 
gas indications of the subdi\nsion and its neighbourhood. 

1910. Clarke, E. de C. : "' Geological Survey of Part of the New Plymouth Subdivision." 

C.-9, p. 19. Contains a brief tentative account, mainly of the geology and oil 
indications of the eastern portion of the subdivision. Concludes that there is as 
yet no geological evidence warranting the definite location of bore-sites. 

1910. J^e Mining Journal 11th, 18t.h, and 25th June: "The Oilfields of New 
Zealand." The issue of 18th June gives a brief but good summary of the 
history of oil-prospecting, and of Hector's, Park's, and McKay's views as to the 
geology of the area. Considers New Plymouth district to be the most promising 
in New Zealand, and concludes that the most hopeful horizon at Motuioa is at 
2,000 ft. or more, but that these oil-bearing strata might be obtained at less depths 
towards Mokau or by going inland from New Plymouth, and that much field 
examination and prospecting has still to be done before existence of a payable 
oilfield in Taranalci can be regarded as proved. 





Outline of Geology . . 


General Sequence of Formations 


General Account of the Structure of 

the Formations . . 


Geological History 


Comparison of Classification of Rocks 

with those of Previous Investigators 


The Onairo Scries . . 




General Distribution 




(1.) Claystones and Sandstones .. 


(2.) Conglomerates 




Interrelationship of the DifiEerent Mem- 

bers of the Series 




Ago and Correlation 


The Pouakai Series . . 
General Distribution 
Structure and Interrelationship of the 

Different Members of the Series 

(1.) Igneous Rocks 

(2.) Claystone Masses, Quartz 

Pebbles, &c. 
(3.) Lignitie Beds 
Mode of Origin 
Age and Correlation 
Pleistocene and Recent Rocks 

Alluvial and Swamp Deposits 
Marine and Fluvio-marine Deposits 
.iEolian Deposits . . 









Outline of Geology. 

General Sequence of Formations. 

The oldest rocks exposed in the New Plymouth Subdivision are a series of claystones, 
sandy claystones, sandstones, and conglomerates, to which from palseontological con- 
siderations a Miocene age is assigned. The name " Onairo," that of a stream in the 
eastern portion of the subdivision, in the watershed of which this series is extensively 
developed at the surface, has been given to these IVIiocene strata. 

Overlying the Onairo Series, generally in apparent unconformity, is a considerable 
thickness of volcanic debris, made up of fragmentary matter of all grades of coarseness, 
from boulders 10 ft. in diameter to the finest ash. Interbedded wnth this material is a 
variable amount of vegetable matter, often only sUghtly carbonized, and sometimes in 
quantities great enough to merit the name of " buried forest." To this series the name 
" Pouakai " is given, it being considered to have originated mainly from the volcanic 
mountain of which the Pouakai Range forms the denuded remains. The age of the 
Pouakai Series is Miocene or ^oimger, but owing to the absence of recognizable fossils 
cannot be definitely fixed. 

Unconformably overlying the Pouakai Series are the alluvial deposits in the valleys 
of the various streams, together with the wind-blown sands forming the dunes along the 
coast-hne, and various marine and flu\ao-marine accumulations. These may be classed 
as Pleistocene and Recent in age. 

General Account of the Structure of the Formations. 
The finer-grained rocks of the Onairo Series are fairly well consoUdated, but never 
at all altered, save that local hardening owing to the segregation of carbonate of lime 
or iron-oxide may occur. \Mierever exposed within the subdivision they are either 
horizontally bedded or very gently undulating. No faulting has been observ-ed within 
the limits of the area imder review, but to the northward a few very sHght and local 
faults have beeu recognized. 


The Pouakai, Pleistocene, and Recent rocks are only exceptionally, and then but 
slightly, consolidated. The stratification of these rocks has remained practicallv hori- 
zontal since the time of their deposition. 

Geological History. 

The probable suecession of events since Onairo times has been sufficiently dealt with 
in the section on physiography. 

Comparison of Classification of Rocks with those of Previous Investigators. 

On the next page is a tabular comparison of the classification adopted in this 
bulletin with the sequence as determined by Hector and Park. 




















J 3 



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Thk Onairo Series. 

The Onairo Series consists of a succession of claystones, sandy claystones, and sand- 
stones, with occasional bands of conglomerate. Th.e base of the series is nowhere seen 
within the subdivision, nor has it been reached in boring for oil near New Plymouth, 
though one of the boreholes has already passed through more than 3,500 ft. of strata 
belonging to the series. 

As shown in the table on page 11, Hector and Park divided the strata described 
here into at least two unconformable series. The combined thickness of these series 
Hector estimated at 4,000 ft. or 5,000 ft. From his own observations the writer con- 
siders that the total thickness of the series is probably more than 5,000 ft. The series 
is, on palicontological gromids. correlated with strata, extensively developed in other 
parts of the Dominion, to which a Miocene age has generally been assigned. 

(Icneral Distrihut ion. 

The Onairo Series is exposed at the surface, or with a coating of the volcanic 
debris of the Pouakai Series so thin as to be negligible, over an area of about 94-4 square 
miles in the eastern portion of the subdivision. The approximate boundary of this area 
is indicated on the geological map of the Waitara Survey District, and runs in general 
slightly east of north from a point four miles and a half east of Huirangi Trig. Station 
to tlie eastern margin of the sul)di vision. It nmst, however, be miderstood that this 
demarcation is a more or less arbitrary one, marking approximately the line along which 
the thickness of the volcanic debris becomes insignilicant. West of this Une the rocks 
of the Onairo Series are to be found outcropping in almost everj* gully as far as the 
Waitara River. 

On the coast-hne they occur continuously (underlying the Pouakai Series) as far west 
as a spot about three-quarters of a mile east of ' Trig. Station IX (Waihi), while at 
Waitara itself the records of the bores of two artesian wells at the freezing-works show 
that the Onairo Series, liere consisting of claystone, is about l(K>ft. below the surface, 
and is overlain by rocks of the Pouakai and Pleistocene and Recent Series. Immedi- 
ately west of the Waitara River a few occurrences of the Onairo Series have been 
found. Again, near the western boundary of the subdivision, at Trig. Station XXVIII 
(Burton's Hill), at a height of between 400 ft. and 500 ft. above sea-level, several out- 
crops of micaceous sandy claystone containing a few Miocene fossils are found near the 
head of a small northward -flowing stream. In the sea-chfEs near the western boundarA" 
of the subdivision masses of well-bedded claystone, sometimes as much iis 5 yards in 
diameter, are found in the agglomerates or breccias of the Pouakai Series. These are 
especially noteworthy («) at the mouth of Waireka Creek (where also small inconstant 
beds of quartz and quartzite pebbles occur), (b) at a point about 20 chains east of the 
mouth of Waireka Creek, (c) to the west of the mouth of Waireka Creek, (d) at the 
mouth of the very small creek running out just on the New Plymouth side of Tokatapu 
Rock, (e) at the bathing-shed near the railway-station at New Plymouth. Beyond tlic 
western boundarj' of the subdivision inclusions of claystone in the agglomerate become 
more numerous, especially between Waikukakuka and Tokataratara, in which neighbour- 
hood the large blocks of claystone show distinct stratification seemingly coincident with 
tliat of the accompanjang beds of volcanic debris. At about 20 chains north-east of the 
mouth of Tapuae Creek is a small but remarkable patch of limestone containing fossils 
apparently differing from those found elsewhere in the Onairo Series.* Smaller lumps of 

* UnfortuuaU'ly these specimens have been mislaid. The writc-r has been unable in the time at his 
disposal to obtain more for purposes of description. A cursory field-examination conveyed the impression 
that species characteristic of the Scinde Island (Napier) limestone were represented. ' 


claystone are to be found in a quarry on a creek about a quarter of a mile south of 
Trig. Station D (Elliot) in Westown, near New Plymouth. They also appear to be 
abundant a quarter of a mile farther up this stream. The finding of a fossil Ostrca in 
the bed of the Henui River seems to point to the occurrence of some Onairo rocks in 
the watershed of this stream. Blocks of claystone are also said to outcrop at German 
Hill, to the south of the subdi\nsion. Although both localities have been examined 
by the \vTiter, neither of these occurrences has been confirmed. 

Records of the boreholes put down inland and near New Plymouth show that the 
Onairo Series imderlies the volcanic debris of the Pouakai Series throughout the sub- 
division. The upper surface of the former series rises gradually towards the interior, 
being, on the average, 200 ft. below sea-level at New Plymouth and 300 ft. above in the 
neighbourhood of Inglewood. 


The rocks of the Onairo Series consist of claystones, sandy claystones, sandstones, 
and conglomerates. 

(1.) Claystones and Sandstones. — Within the New Plymouth Subdi\'ision the greater 
part of the series consists of soft calcareous claystones, which are frequently somewhat 
sandy, and occasionally pass into rather incoherent, often abundantly micaceous, sand- 
stones. It may be said in general that these finer-grained rocks grade imperceptibly 
into one another. No success attended the attempt to trace any particular band of 
sandstone or claystone for more than a short distance. Towards Mokau an extensive 
development of sandstones, with limestone and coal, is foimd. Small coaly partings 
occasionally occur in the finer-grained rocks of the Onairo Series, and are especially 
noticeable near the gravel-quarry on the Okoke Road near its junction with the Mokau 
Road. The claystones and sandstones are often fossiUferous. The rocks under dis- 
cussion frequently, especially in the south-east comer of the subdi\asion, contain hard 
calcareous nodules which have been formed by the segregation of carbonate of lime 
during, or after, the consolidation of the enclosing strata. Within the subdivision these 
concretions usually have a spherical or ellipsoidal form, and are disposed in lines parallel 
to the planes of stratification. On the east side of the valley of the Mangahewa Stream, 
however, two bands of such concretions are seen to be distinctly inclined to one another, 
the upper band cutting obUquely across the bedding of the claystone. In the cUfEs 
bordering the sea on the northern boundary of the subdi%ision the concretions are 
irregular in shape, and have their long axes at right angles to the planes of stratification. 
Similar fantastically shaped nodules are to be seen in the chfi just south of the mouth 
of the Mohakatino River. In a small stream entering the headwaters of the Urenui 
River from the west the concretions are prismatic in shape. The concretions are 
rarely united to form continuous bands. They are the hard streaks frequently referred 
to in records of bores. 

Small crystals of pyrite are almost always to be found in the claystones and sand- 
stones. The following is an analysis of a typical sample of Onairo claystone from the 
cliffs in the Waitara River, near the southern boimdary of the subdivision : — 


Alumina (AljOj) 


Ferric oxide (FegO,). . 


Lime (CaO) 


Magnesia (MgO) 


Alkalies (KjO and Na^O) 


Carbonic anhydride (COo) 


Moisture and organic matter . 




The following analysis* of " clay from Urunui [Urenui] " is of interest, as the clay 
(almost certainly of the Onairo Series) was that which the late l\Ir. E. M. Smith sometimes 
used in iron-smelting (see postea, p. 50) : — 


. . 62-93 



Manganese . . 

. . Traces 

. . Traces 






Carbonic acid 


Sulphuric acid 
Titanic acid 

. . Traces 

Wat«r and organic matter 



2. Conglomerates. — The conglomerates occur in the finer sedimejits described above, as 
hands, commonly about 1 ft. in thickness, but varying in different localities from a few inches 
\ip to 10 ft. or 12 ft. The conglomerates are. as a rule, little consolidated, save where cemented 
by calcareous matter derived from fossil remains, which they very frequently contain. The 
fragments of which the conglomerates are composed vary from minute pebbles to small 
boulders that but rarely reach 6 in. in diameter. All are well-rounded and water-worn. 

A study of hand-specimens and of microscopic sections of pebbles from the conglomerates 
shows that the usual constitueiits arc quartz, quartzite. and jasperoid argillite. Fragments 
of grauwacke. and possibly of diorite. are also rather conmion. The material of which the 
conglomerates are composed is evidently derived from a complex of old sedimentaries and 
intrusives lying to the east of the area under review, which makes up the structural axis of 
the North Island. The sedimentaries of this complex were at (me time usually referred to 
the Maitai Series, of supposed <'arboiiifernus age, by tin- staff of the Geological Survey, but 
during recent years the age i>f thf rocks |)iaced in the Maitai Series has been generally 
considered an open fjuestion. 


Since t\v Uiian-ii ;?i.ries contains apparently the dui-l pctrohferous strata of the area 
under consideration, the main object of the rec^ent geological survey was to arrive at a know- 
ledge of the structure and arrangement of the various members of the series, wnth a view to 
the location of anticlines and s^nidines. in which, according t.<) the very generally accepted 
■' anticUnal" theory, the oil might be expected tio havi- accumulated. With this object, as 
many rehable strikes and dips as possible were noted and plotted on the geological maps. 
As a rule, the finer-grained rocks of the Onairo Series exhibit fairly distinct lines of strati- 
fication. A local exception to this rule is found in the fine claystones exposed in the upper 
waters of the Onairo Stream, which are singularly devoid of bedding-planes. 

As already noticed, the streams of the subdivision flow nearly to thfir headwaters 
through alluvial deposits. Therefore few outcrops of Onairo rocks are to be found in the 
actual watercourses, except near their sources. It thus follows that the majority of the 
strikes and dips recorded had to be obtained on the sides of spurs some distance from the 
streams, on faces exposed by landslips, or in road-cuttings and quarries. It seems probable, 
therefore, that, though care was taken to record only those observations made in strata un- 
disturbed by surface-slipping, a certain amount of sagging may have taken place along large 

* ■■ Fifth Annual Report of tho Colonial Museum and Laboratory," 1870, p. 12. 
2— New Plymouth. 


exposed faces of such soft strata as those under consideration. When the prevailing low 
angle of dip is remembered, it is e\ndent that the liability to error in recording the 
stratification is groat. 

A careful plotting of the most reliable strikes and dips has failed to reveal the existence 
of any persistent anticlines and synclines. The strata under consideration dip to all points 
of the compass, but on summarizing it is found that the westerly dips outnumber the easterly 
in the proportion of three to one. The more exact directions of the westerly dips are di\-ided 
almost equally between soubh-west, west, and north-west, but in the south-east portion of 
the subdivision a slightly preponderant number are to the south-west, while in the nortl'- 
east portion the dip is more usually to the north-west. The dips aie always at low angles, 
usually less than 10°, only ten or twelve instances of dips of 15° or more, and about the same 
number of dips at angles between 10° and 15°, having been observed. Of these higher dips 
a few more are westerly than easterly. It thus appears that the rocks of the Onairo Series 
are arranged in gently undulating fashion, but are in general dipping in a westerly direction. 
There is some indication that they form the western end of a westerly-pitching anticlinorium, 
the axis of which runs in a north-west and south-east direction. 

Evidence obtained towards Mokau, beyond the eastern limits of the subdivision, shows 
that the calcareous claystones which predominate in the New Plymouth Subdivision are 
underlain in descending order by (1) rapidly alternating sandstones and claystones, (2) sand- 
stone in thick beds together with Hmestone and occasional coal-seams. 

Outside the subdivision, from the White CHiis to Awakino, small local faults in the rocks 
of the Onairo Series are of fairly frequent occurrence. The largest faults observed were in 
the Maryville Coal-mine, on the Mokau iRiver, where one or two quite local dislocations with 
a maximum throw of 6 ft. to 8 ft. have been disclosed in the workings. Within the sub- 
division no actual faults were observed, but in seven localities the topography seems to indi- 
cate that subsidence of small blocks of strata including Onairo rocks has occurred. These 
localities are specially indicated on the maps, and are situated — (1) in the acute angle formed 
by the junction of the Richmond and Ackworth Roads ; (2) on the west side of the Richmond 
Road, about half a mile beyond its junction with Lincoln Road : (3) near the iMangahewa 
Road, about half a mile from its junction with the Otaraoa Road ; (4) at the headwaters 
of the iiVIangaonga Stream ; (5) near the headwaters of the Mangaonga Stream ; (6) just out- 
side the eastern boundary of the subdi\asion, about half a mile north of Jimction Road ; 
(7) at the Rotokare or Ratapihipihi Lagoon, two miles south of New Plymouth. No un- 
doubted occurrences of Onairo rocks in situ are found near Nos. (1), (2), (3), and (7) of 
the locahties mentioned. The depressions may therefore be due to subsidences in the over- 
lying volcanic debris of the Pouakai Series alone. In the other three localities mentioned 
there can be little doubt but that local basin-faulting in which the Onairo rocks were con- 
cerned has recently taken place. There is apparently no structural relationship or community 
in origin between these depressions, the main structural features cflthe Onairo rocks, and 
the occurrence of gas or oil indications. 

IrUerrelntionship of the Different Members of the Series. 

Since the conglomerate bands already described are the only beds in the Onairo Series 
with distinctive petrological characters, the writer attempted by means of repeated observa- 
tions of strike and dip and barometric heights to establish for them definite horizons in the 
series. It may be said in general that the conglomerates appear to occur at two different 
levels in the series, separated by about 200 ft. of the finer sediments. 

In his reports on the Taranaki District Hector divided the Onairo Series into three 
distinct formations of Cretaceo-tertiary, Eocene, and Lower IVIiocene ages. He considered 
the unconformity between the Cretaceo-tertiary and the Eocene series to occur on the Mokau 
River, and that between the Eocene and Lower Miocene to be seen near the northern end of 


the \\Tiite CiiSs.* In his earlier report he classed the rocks, which he later referred to the 
Lower Miocene, as older and newer Tertiary, separated by a marked unconformity at the 
mouth of the Omera (Onairo). and with the newer Tertiary he included the greater part, of 
the Pouakai Series of this report. In his later paper, however, no mention is made of this 
unconformity, and his classification is as stated above. Further notes regarding this point 
will be given later. In this, as in most other important points, the later observers, McKay 
and Park, appear to be in general agreement with Hector. Park in his reportf di^^des the 
rocks in question into Cretaceo-tertiaiy and Upper Miocene, and. though he does not describe 
it. shows in his map an luiconforraity between the two series at Tongaporutu. He mak^s 
no reference to Hector's unconformity between Pliocene and Miocene at Onairo. 

The \vriter has been unable to find the evidence for the imconformity which according 
to the above geologists separates the lowest part (Cretaceo-tertiary beds) of the Onairo Series 
from the overlying portion. Apparent unconformities may sometimes be recognized at 
various horizons, as, for example, between a sandy claystone and a quattzose conglomerate 
at Corkill's quarry, in the south-eastern corner of the subdivision, but these are due to current 

The following brief account of the strata forminjj the lower portion of the series under 
discussion, which are exposed mainly along the sea-front between Pukearuhe and Awakino, 
may be of interest. 

In the neighbourhood of Tongaporutu the claystoncs and sandy claystones that fo m 
the sea-clifEs to the south tend to pass into soft sandstones arranged in beds as much as 25 ft. 
in thickness. The sandstones are interbedded with the claystones, and represent the same 
period of sedimentation. Farther north, between Hapanui and Awahaehae streams, the low 
chfis are composed of an impun; green sandstone, overlying which in apparent conformity 
is claystone. In the neighbourhood of Kawau Pa the rocks consist of 6 in. beds of clay 
separated by thin partings of sand, and overlying all is a bed of yellow sandstone about 7 ft. 
thick. About two miles farther on beds of greensand are separated by thin partings of clay, 
and at the Mokau Heads a y(>llow sand overlies a claystone in which is a thin layer of pebbles, 
apparently andesite. 

Between the Mokau Heads and the Awakino Heads beds of sandstone about 18 in. in 
thi kness alternate with seams of clay about Sin. thick. These an^ underlain at the south 
Awakino Head by a fine well-bedded grit, containing abundant hornbhuide crystals, which 
in turn is underlain by a bryozoan limestone. 

On the Awakino -Te Kuiti Road, about halfway up the Taumatamaere Hill, decom- 
posed gtauwackcs and argillites containing apparf^ntly Tiiassic fossils are overlain by sandy 
claystones with abimdant Miocene fossils. It seems probable that these claystones underlie 
the Umestones mentioned above. 

The section obtained by following the Mokau River as far as the Maryville Coal-mine 
requires much careful examination, but. so far as the writer could observe, the general 
seqtience seen between Mokau and Awakino holds good, save that there is on the Mokau an 
extensive development of coal-seams, with accompanying sandstones, in the strata under- 
lying the hmestone. 

PalcBontology . 

Though seldom very abundant, fossils can be {(umd in most exposures of the Onairo 
rocks. They are most nuinerouH in the bands of the upper conglomerate horizon exposed 
in the headwaters of the Urenui River and its tributaries, and in thi' sandy claystone which 
forms the sea-front between Urenui Township and the mouth of the Mimi River. The fol- 
lowing list includes, so far as is known, all the specifically identified fossils which have been 

* Rep. G.S., 1878-79, p. 21. [It is not quito clear whether Hector considered an unconformity to exist 
at the White Clifis or not.— P. G. M.] 

t R«p. G.S., 1886-87, vol. xviii, p. 57. On p. 60 Park says that " there is no stratigraphical break in 
the sequence of the Tertiary strata from the lowest to the highest beds." 

2*- New Plymouth. 


found in or near the New Plymouth Subdivision either by the writer or by previous investi- 
gators. The names are given in the first column, whilst in the second is entered the name 
of the first collector to report the species from the subdivision or its neighbourhood. In the 
third column is placed the range of the species. This is taken wherever possible from an 
impublished summary* of the Tertiary formations in New Zealand in the possession of the 
New Zealand Geological Survey. AVhen the species is not mentioned in that paper the range 
is generally taken from Mutton's Catalogue of the Tertiary Molliisca and Echinodcrraata 
of New Zealand. 


First Collector. 


FlabeUum laticostatum Teuison- Woods 
Trochoci/athus mantelli Milne-Edwards 


Xucula nitidula Adams 
Solenella australis Zittel 
Ciicullcea aUa Sowerby . . 

Ldmopsis (Trigonocoelia) insolita Sowerby 

Glycimeris (Pectunculus) laticostatus Quoy 

G. (Pextunculus) r/lobosus Harris . . 

Pecten fischeri Zittel 

Pseudamusium (Pecten) hochstetteri Zitt<il 

Lucina divaricata Lamarck 

Cardium striatulum Sowerby 

Dosinia grayi Zittel ... 

Cyclina dispar Hutton . . 

Vpmus (Chione) mesodesma Quo\' 

V. (Chione) stutchburyi Gray 

Meretrix (Cytherea) acuminato Hutton 

Tellina deUoidalis Lamarck 

Mytilicardia excavata Deshayes . . 

Maclra cequilalera Reeve 

Zenatia acinaces Quoy . . 

Teredo heaphyi Zittel . . 


Uenlalium ecoslatum Kirk 
D. giganteum Sowerby . . 
D. nanum Hutton 

Crepidula incurva Zittel 
Natica (Mamilla) nvata Hutton . . 
iV. vitren Hutton 
Turritella (Zaria) tricincta Hutton (= T 

rosea of Mantell) 
C'assidaria sulcata Hutton 
Struthiolaria tuberculata Hutton 
Buccinum robinsoni Zittel 
Cominella maculata Martyn, var. b 
Sipkonalia nodosa Martpi 
Ancilla australis Hutton 
Pleurotoma tuberculata Kirk 

Clarke . . Upper Oamaru. 

Clarke . . *Middle Oamaru (Waikouaiti beds). 

Park . . Recent. 

Park . . Upper Oamaru and Wangauui. 

Clarke . . *Lower Oamaru (Waihao green- 

Clarke . . *Upper Oamaru (Pareora beds). 

Park . . Oamaru-Recent. 

Clarke . . *Upper Oamaru (Pareora beds). 

Clarke . . Upper Oamaru. 

Clarke . . Upper Oamaru. 

Park . . Oamaru-Recent. 

Park . . Upper Oamaru-Recent. 

Park . . Upper Oamaru and Wanganui. 

Park . . Doubtful. 

Park . . Upper Oamaru-Recent. 

Park . . Upper Oamaru-Recent. 

Clarke . . Upper Oamaru. 

Park . . Pleistocene and Recent. 

Park . . Wanganui and Recent. 

Park . . i Pleistocene and Recent. 

Park . . Upper Oamaru-Recent. 

Clarke . . *Lower Oamaru (Waihao green- 

Park . . Upper Oamaru and Wangauui. 

Park .. *Middle Oamaru (Waikouaiti bexis). 

Park . . Wanganui. 

Park . . I Upper Oamaru. 

Park . . Upper Oamaru and Wanganui. 

Park . . Wanganui-Recent. 

Park . . Upper Oamaru-Recent. 

Park . . Upper Oamaru. 

Park . . Upper Oamaru. 

Park . . Upper Oamaru. 

Park . . Upper Oamaru-Recent. 

Clarke . . [ Upper Oamaru-Recent. 

Park . . Upper Oamaru-Recent. 

Park . . Wanganui. 

* Drawn up mainly bj- Professor Park. Species marked with an asterisk (*) are regarded by this author 
as characteristic of the horizon to which they are assigned. 


Age and Correlation. 

From the evidence given on previous pages it appears that the Onairo Series consists 
of a conformable succession of rocks. A consideration of the ranges of the fossil species 
enumerated in the preceding section leads to the conclusion that the series is of Oamaru 
(Miocene) age. In petrological character and in fossil-contents the rocks in question show 
a very close rf.semblan( c to strata in the northern part of the South Island to which a 
similar age has been assigned.* 

The Pouakai Series. 

The Pouakai Series consists of a succession of beds, generally of fragmental volcanic 
material, sometimes water-worn, but usually angular or subangular, with which are inter- 
bedded, in places, rather extensive lignitic deposits and inconsiderable layera of thoroughh- 
water-worn pebbles of quartz, quartzit«, grauwacke, and argillite. In one place have 
been found rare fragments of baked or reddened claystonet of the Onairo Series. The 
flow rocks, probably of somewhat earlier date, which form the Sugar-loaves near New 
Plymouth are also included in this series. From data derived from the records of 
various bores, together with a consideration of the height of the country composed of 
the rocks of this series, the writer estimates that within the subdivision it has a 
maximum thickness of about 700 ft. 

General Distribution. 

The Pouakai rocks may be regarded as covering an area of about liS'G square miles 
within the subdivision, though a thin covering of volcanic material extends almost to the 
eastern and south-eastern boundaries, where, on the geological map, it is not represented. 
Further details regarding the di.->trib tion of the Pouakai rocks have ;ilready been given in 
dealing with that of the Onairo Series (pp. 1.5, Ifi). 

Structure and IrUerrelationshif of the Different Members of the Series. 

The rocks of the Pouakai Series are horizontal, occasional apparent departures 
from this rule being due to false or current bedding. In general it may be stated that 
the lower part of the series contains both the more coarsely grained material and the 
lignitic deposits which are usually, though not invariably, absent from the upper portion 
of the series. The beds of wat«r-woni pebbles of quartz, quartzite, &c., are found appa- 
rently only at the base of the series. The conical hills around Inglewood and near 
Lepperton, of which mention has already been made, consist usually, but not invariably, 
of large angular boulders irregularly mixed with finer volcanic material, generally showing 
a rude bedding with predominant dip to the south-east. 

A good idea of the succession of beds in the Pouakai Series is obtained by an examina- 
tion of the coast-line between New Plymouth and the mouth of the Oakura Stream, about 
two miles and a half south-west of the western boundary of the subdivision. In the low^ 
cliff forming the sea-front at New Plymouth well-bedded volcanic sand is seen to overlie, 
conformably, a coarse breccia. A few chains east of Paritutu a fine volcanic sand, apparently 
identical with that just mentioned, tmconformably overlies an agglomerate, which in turn, 
at the base of the eastern slope, unconformably overlies the effusive rocks of which this 
Sugar-loaf is composed. Breccias and agglomerates, containing in places rocks 10 ft. and 
more in diameter, but sometimes of only moderate coarseness, form the sea-cliffs to the 

• See Bulletin No. 3 (New Series), N.Z.G.S., p. 51. 

t The occurrence of these was pointed out to the writer by Dr. J. \\'anner, of Bonn University. 


Koutli-vve»t of Paiitutu ; but in many plac«s, more especially between the mouth of the 
Oakura Stream and the western boundary of the subdivision, coarse agglomerate beds 15 ft. 
or more in thickness alternate with fine-grained fragmental material. In this neighbour- 
hood, as noted in the section on the Onairo Series (p. 15), inclusions of sedimentary 
rocks containing Miocene fossils are of frequent occurrence. Small beds of water-worn 
pebbles of quartz, quartzite, and other rocks also occur. Pebble-beds of this descrip- 
tion are, however, most frequent to the north-east of the subdivision, just north of the 
White Cliffs, where they directly overlie the claystones and sandstones of the Onairo 

Inland, wherever the rocks of the Pouakai Series are deeply dissected by watercourses, 
the same general succession as that exhibited on the coast-line may be recognized more 
or less satisfactorily, the lower beds containing a much larger proportion of agglomerate 
than the upper. 


(1.) Igneous Rocks. — The igneous rocks of the Pouakai Series are generally but little 
decomposed. Notable exceptions to this rule are the rocks found in Smart Road and 
elsewhere. These are further described in Chapter III, p. 52. 

Numerous samples of the igneous rocks of the Pouakai Series were collected by the 
writer, but for various reasons microscopic sections of the majority of them are not available 
for examination at the time of writing. From a megascopic examination, and from the 
results of chemical analyses, the writer believes that, though they show little or no 
peculiarity in chemical composition, the Sugar-loaf rocks may on petrological grounds 
be separated from the rest of the rocks of the Pouakai Series, being (with the exception 
of those of Mikotahi) characterized by the frequent occurrence of masses of hornblende 
crystals often several inches in diameter, and by the presence of feldspar crystals 
which are | in. in length. These feldspar's are described by Hutton* as sanidine, and 
he calls the rock a trachyte. Subsequently, however, he statedf that since plagioclase 
is more abundant than sanidine in the rock, and since the rock is foimd to contain 
only 53-43 per cent, of siUca, the name should be altered to hornblende-andesite.J 

Specimens of Pouakai igneous rocks collected from other parts of the subdivision, and 
from some localities a little to the south of it, differ from the Sugar-loaf rocks chiefly 
in the greater abundance, and more even distribution through the rock-mass, of phenocrysts 
of ferro-magnesian minerals. A small series of microscopic sections of Pouakai rocks from the 
agglomerates exposed near the southern boundary of the subdivision, chiefly in the valley 
of the Waitara River, contains representatives of hornblende- and augite-andesites agree- 
ing very closely in structure with specimens of andesites from the Whangaroa Subdivision.§ 
The hornblende crystals are dark broAvn and strongly pleochroic, always surrounded by opaque 
resorption-bands. In some cases the hornblendes have disappeared completely, leaving 
their characteristic forms outlined by scattered crystals of magnetite. The augite crystals 
are pale-yellowish -green in colour and show sharp unaltered margins. A few crystals of 
hypersthene are occasionally present. In the hornblende-andesites augite is always present, 
but in some sections showing numerous augite crystals hornblende is absent. Hutton 
describesll hornblende-, augite-, and olivine-andesites from Mount Egmont, and an andesite 
from the Sugar-loaves in which enstatite is present, but in lesser quantity than augite. 

The following are analyses of Pouakai rocks from eleven different localities. For 
comparison are added three typical analyses of andesites from the agglomerates of supposed 

* Journal and Proc. Roj-al Society N.S.W., vol. xxiii, p. 126. 

t Trans., vol. xxxi, p. 484. 

X 1 made a section of tliis rock some years ago in which all the feldspar is triclinic. — P. G. Moroak. 

§ Bulletin No. 8 (New Series), N.Z G.S., 1909, pp. 66-67. 

II Joiu-nal and Proc. Royal Society N.S.W., vol. xxiii, pp. 133-42. 


Miocene age, which attain a wide distribution in the northern part of New Zealand. It will 
be seen that the Taranaki rocks analysed show on the average a somewhat lower 
silica-content. It will also be observed that the rock from Mount Egmont differs in no 
important respect from the general type of the igneous rocks belonging to the Pouakai 
Series. On the other hand, the Paritutu rock, originally described by Hutton as a 
trachyte, is somewhat more acidic than the general type, according to analysis No. 11 in 
the following table : — 








Silica (SiOj,) 








Alumina (AljOj) 








Ferric oxide (FejOj) 








Ferrous oxide (FeO) 








Manganous oxide (MnO) 








Lime (CaO) 








Magnesia (MgO) 








Potash (KjO) 








Soda (Na^O) 








Titanium -dioxide (TiOj) 








Phosphoric anhydride (PjOj) 

. . 



Carbonic anhydride (COj) 



Less on ignition 









100-27 lUO-30 10013 100-40 UX)-32 100-15 100-34 








Silica (SiOjJ 








Alumina (AI^Uj) 








Ferric oxide (Fe^O^) 








Ferrous oxide (FeO) 








Manganous oxide (MnO) 








Lime (CaO) 








Magnesia (MgO) 








Potash (K,0) 






2- 15 


Soda (Na^O) 








Titanium-dioxide (TiOj) 








Phosphoric anhydride (P^Og) 





Carbonic anhydride (COj) 








Loss on ignition 









Localities of above analyses 

(1.) Outcrop of boulders on Junction Koad near Kent iload. 

(2.) Quarry near Sentry Hill flour-mill. 

(3.) Quarry near Moa Company's bore, Inglewood. 

(4.) Quarry on Egmont Road, at bridge over Ngatoromarama Stream. 

(5.) Quarry on Otaraoa Road. 

(6.) Railway ballast-pit near Sentry Hill quarries. 

(7.) Atuakake Creek, near Carrington Road. 

(8.) Mangoroi Creek, near southern boundary- of the subdivision. 

(9.) Smart Road — undecomposed igneous rock found occasionally in the 
(10.) Waiwakaiho River, near its source on Mount Egmont. 
(11.) Seaward face of Paritutu. 
(12.) St. Paul's, WTiangaroa, North Auckland. 
(13.) Beeson's Island, Coromandel Peninsula, Auckland. 
(14.) Coal Point, near North Cape 


99-95 99-64 99-81 99-86 100-00 99-96 100-00 







uding sulphur) 

. 21-95 

The following analysis shows the composition of a rock from the Pouakai Range, which 
has apparently been altered by hydrothermai action : — 

Silica (SiOj) 46-77 

Alumina (AlgOj) 
Ferric oxide (FeaOj) 
Lime (CaO) 
Magnesia (MgO) 
Iron-disulphide (FeSj 
Loss on ignition (exc 
Alkalies and undetei-mined 


(2.) CUiijstone Masses, Quartz Pebbles, <fec.— The distribution of the masses of clay- 
stone containing Miocene fossils and occurring in the agglomerates of the Pouakai Series 
has been sufficiently described under the heading of " Onairo Series" (p. 15). Small 
bands of water-worn pebbles of quartz, grauwacke, &c., are occasionally foimd, especially 
near the base of the series. In the gravel-pit near the gas-vent on Mr. Bishop's farm 
(see p. 44) fragments of baked and reddened claystone are occasionally found amongst 
the volcanic boulders, as already noted on p. 21. 

(3.) Lignitic Beds. — The lignitic beds of the Pouakai Series occur most abundantly 
on the lower coastal plain between Bell Block and Urenui, where the great majority 
of household wells strike, at a depth of between 15 ft. and 30 ft., a layer of tree-trunks 
mixed with remains of smaller vegetation and with tufa and volcanic boulders, which 
continues for about 12 ft. to 20 ft. The same deposits, though not so strongly developed 
perhaps, occur in the high country inland fringing the Tapuae-Manganui Ridge. Proof 
of this is obtained in many of the road-cuttings and natural sections, and also in the 
various boreholes which have been put down in search of oil. Large deposits of similar 
material are said to have been encountered in the long tunnel driven in connection 
with the hydro-electric lighting scheme for New Plymouth. This timnel cuts across the 
great bend of the Waiwakaiho River above its junction with the Mangorei Stream. 

In the south-west corner of the Waitara Survey District lignitic deposits of a 
difierent type from those just described, but probably contemporaneous with the Pouakai 
rocks, are found over an area of about 96 acres, as indicated on the geological maps. 
These deposits consist of 12 ft. to 20 ft. of alternating layers of sand and impure peaty 
lignite. The sand is made up of fragmentary crystals of ferro-magnesian minerals and 
of very decomposed feldspars. In the upper layers the bands of sand are the thicker, 
whereas towards the base the lignite layers become predominant. 

Mode of Origin. 

The fragmental rocks ot the Pouakai Series are, as already noted, ahnost entirely 
volcanic in origin. From the chemical and petrological characters of the rocks as 
detailed above it seems likely that the volcanic rocks originated mainly from the 
volcano or group of volcanoes which occupied the site of the Pouakai Range. From 
the water-worn character of the majority of the boulders, and the bedding exhibited, 
it would seem that the rocks were accmuulated under water. It must be noted, 
however, that Dr. Wanner, of Bonn, who during his visit to the district in November 
of 1910 drew the writer's attention to the occurrence of baked claystone fragments 
near the Mangaone Stream (see p. 21), considers that there is e\ndence for the existence 
of a volcano in this neighbourhood in Pouakai times. Moreover, the coarse rudely 
bedded deposits of angular boulders which form the conical hills near Lepperton and 
Inglewood (see pp. 5, 21) are best explained as ha%'ing originated from one or more vents 


in the vicinity. The same is true of the boulders forming a knob on the south bani< 
of the Waitara Kiver, near the mouth oi Maugaoue Creek, aud occurring in the quarry 
on the Otaraoa Road, about one mile north of the southern boxmdar}- of the sub- 

As already noticed (p. 21), the lava-fiows forming the prominent hill of Paritutu, 
near the New Plymouth Breakwater, are apparently overlain unconformably by a coarse 
volcanic breccia of the Pouakai Series. The exceedingly steep sides of Paritutu, which 
are due almost entirely to aerial erosion, are seemingly continued below the mantle 
formed by the breccia. This fact and the petrological difiereiices between the lavas of 
the Sugar-loaves and the volcanic debris constituting the main part of the series mider 
consideration (see above, pp. 22, 23) render it highly probable that some apace of time 
separated the extrusion of these lava-flows from the deposition of the rest of the 
Pouakai rocks. 

The apparent miconformity near Paritutu (referred to on p. 21) between the coarse 
breccia mentioned above and a fine volcanic sand is probably only local, since sand of 
the same character is seen conforjuably bedded with coarse breccia in the cliffs fronting 
New Plymouth and also near the western boundary of the subdivision. 

It would seem, therefore, that the rocks of the Pouakai Series accumulated in 
rather an intermittent and spasmodic fashion (as might, indeed, be expected from their 
almost entirely volcanic origin), partly on land and partly in shallow water. 

Aye and Corretatwn. 

The only fossils as yet found in the rocks of the Pouakai Series are the carbonized 
remains of plants, apparently identical with species at present growing in the district, 
but these do not afford aiiy clear proof of age. Some e\'idence, however, as to the 
geological age of the rocks in question may be obtained from the relationship of the 
series to the preceding and succeeding ones. 

Only two clear sections showing the relationship of the Pouakai and Onairo Series were 
seen — namely, on the sea-cotist about three-quarters of a mile east of Trig. Station IX 
(Waihi), and on the Mangaone Road a short distance south of the southern boundary 
<»f the subdivision. In these places there seems to the writer to be decided uncon 
formity between the two series. Again, at the swinmiing-baths near New Plymouth 
are fomid the erect carbonized stumps of trees, the roots of which ramify through the 
masses of claystone referred to above (p. 15) as possibly belonging to the Onairo Series. 
These trees are merlain by water-borne deposits of the Pouakai Series. If the clay- 
stones belong to the Onairo Series, and if they are in situ, an unconformity is clearly 
indicated in this locality. 

On the sea-coast near the western bomidary of the subdivision the remarkable 
occurrence of masses of claystone containing Miocene fossils has already been noted 
(pp. 15, 22). The large size of some of these masses makes it seem probable that they 
are in situ. If this be so, the concordance of bedding between these sedimentaries and 
the fragmental volcanic rocks of the Pouakai Series points to a conformity here between 
the two series. On the whole, however, the exidence seem.s to indicate that the Pouakai 
Series overlies the Onairo Series unconformably, though probably no great lapse of 
time is thus indicated. In this connection it is interesting to note that the volcanic 
breccias oi the Manukau Heads, near Auckland, are generally considered to succeed 
the Miocene strata of the Waitemata beds conformably, and are similarly seen to do 
so at Parengarenga, near the North Cape. ' 

♦ UeU and Clarke : " A (.ifological Keconnaisaancc ol Northfriiiiiosl Sew Zealand.' TranB., vol. xln 
(19C>9). i>. nio. 

The rocks of the Pouakai Series are seen in many places to be unconformably 
succeeded by the Pleistocene and Recent deposits, to be described later. 

As mentioned in the section on petrolog}-, the volcanic rocks of the Pouakai Series 
show a strong resemblance to the andesitic agglomerates, breccias, flows, and dvkes of 
remarkably constant chemical and petrological characters, which attaiji a wide distri- 
bution in the northern part of New Zealand, and to which a Jliocene age is generally 
assigned.* Much detailed petrological and field work, especially along the coast-Une 
between Mokau and the Manukau Harbour, must be carried out before the correctness 
of any correlation between the Pouakai Series and the supposed Miocene volcanic 
rocks of Northern Auckland becomes more than a probability. This correlation, if it 
be established, together with the evidences of a probably inconsiderable lapse of time 
between the deposition of the Pouakai and of the Onairo rocks, makes it reasonable 
to conclude that to the majority of the rocks of the former series should be assigned 
an Upper Miocene and Pliocene age. It should be noted that there is no e\adence 
of any break separating the main part of the Pouakai Series from the latest accumu- 
lations due to the eruptions of Momit Egmont : also that the Kaitaki (Patua) Range 
is composed of volcanic rocks much more decomposed than the majority of the Pouakai 
rocks, and probably, therefore, either more or less contemporaneous with or older than 
the Sugar-loaf rocks. 

It must be mentioned here that Marshall! considers the Pouakai rocks to be 
yomiger than the rhyohtes of the Central Plateau, and therefore altogether distinct in 
age from the Miocene volcanics of Northern Auckland. 

Pleistocene and Recent Rocks. 
Pleistocene and Recent rocks are of widespread occurrence throughout the sub- 
dnision, but nowhere cover any very large area. The accumulations consist of gravels, 
sands, and muds, with very hmited quantities of bog iron-ore. None of the deposits 
are more than very slightly consolidated. The materials under consideration may be 
di\nded into alluvial and swamp, marine and flu\ao-marine, and teolian deposits. 

Alluvial and Swamp Deposits. 

The alluvial deposits consist mainly of silts, gravels, and sands of all degrees of 

The predominant alluvial deposits in the western portion of the subdivision are 
gravels and sands derived by erosion from the rocks of the Pouakai Series. These 
deposits are usually rather fine-grained, except in the actual watercourses, where large 
boulders may be seen. Silts formed from the claystones and sandstones of ths Onairo 
Series are predominant in the valleys of the streams in the eastern portion of the 
subdivision. These silts always contain a smaU amount of ironsand derived from 
the volcanic rocks of the Pouakai Series, which, as already not€d, form in many places 
a thin covering over the Onairo rocks. In the small tidal inlet at the mouth of the 
Mangaoraka Stream there are found near low-water mark a few beds of clay alternating 
with peaty matter. These beds are overlain by gravels containing pebbles up to 2 in. 
m diameter. The occurrence of this probably lacustrine deposit below sea-level points 
to a slight amount of depression in recent times. 

♦ Concerning these rocks see Bulletin No. 8 (New Series), N.Z.G.S., 1909, pp. 68-69, and literature cited 

rAust. Ass. Adv. Sci., vol. x, p. 376. 


Small swamps containing clayey deposits mingled with much carbonaceous matter 
are of wide occurrence throughout the subdivision, except near the headwaters of the 
streams which drain a land surface of Onairo rocks. In many places inconsiderable 
deposits of bog iron-ore have been formed in the small swamps, notably in the country 
near the upper (southern) part of Smart Road and Dorset Junction Road. 

In a swamp near the head of the streamlet which flows north-west just north of 
Trig. Station D (Elliot), in Westown, a small deposit of infusorial earth occurs. The 
following is Dr. Maclaurin's report on a sample : — 

The sample was dried at 

Silica (SiOj 
Alumina (AI2O3) 
Ferric oxide (Fe^,U.,) 
Lime (CaO) 
Magnesia (MgO) 
Loss on i-niition 

100° C. and analysed, with the following results 


" The sample is mainly infusorial earth." 


Of interest also are the peaty deposits which are exposed round the gas-vents in 
the upper waters of the Huatoki Stream, and which are also found in the upper waters 
of the Mangahewa and Puketotara streams, where they possibly mark the sit« of former 
gas-vents. The following is Dr. Maclaurin's report on three samples — (1) from Manga- 
rewa Creek, (2) from Puketotara Creek, (3) from the neighbourhood of the gas-vents 
on Grooby's Farm (see Chapter III, p. II): — 

" The samples were dried on a water-bath and analysed, when they proved to be 
peats of tlie following composition : — 

Organic matter 

Ash . . 






73- 1 








" No infusoria were detected in the ash." 

Marine and Fluvio-marine Deposits. 

In the neighbourhood of the outcrops of coarse agglomerate, which occur chiefly 
along the western portion of the sea-coast of the subdivision, the beach deposits consist 
of rounded volcanic boulders of all sizes. With this exception, the marine and fluvio- 
marine deposits are formed almost exclusively of the well-biown " Taranaki ironsands." 
These ironsands are black in colour, and apparently consist mainly of magnetite, ihnenite, 
and ferro-magnesian minerals derived from the decomposition of the rocks of the Pouakai 
Series. The fragmentary crystals of zincblende which are fairly frequent in the iron- 
sand near the New Plymouth Breakwater are probably derived by denudation from 
the Kaitaki (Patua) Range, where this mineral is known to exist. Several other 
metals said to have been found in the ironsand in the neighbourhood of the Breakwater 
are probably derived from wrecks or such extraneous sources. The ironsands are further 
dealt with in Chapter III, p. 48. 


Mnlian Deposits. 
The aeolian deposits form the sandhills, the distribution of which has been suf- 
licioutly described in Chapter I, p. 6. These deposits consist ahnost entirely of 
"ironsand." In places the sand has been cemented by the deposition of iron-oxide, 
more especially where temporary swamps occur on the surface of the sand-dunes. On 
the Mokau Road, in the cuttings on the north bank of the Mimi Stream, loosely con- 
solidated sands containing a considerable proportion of " ironsand " are seen. The same 
sands are found on the Tupari Road about three-quarters of a mile beyond its junction 
with the Okoke Road, and, unconformably overljing the Onairo rocks, on the sea-coast 
near the north-east boundary of the Waitara Survey District. These sands are appa- 
rently aeolian in origin, and, since no sand-dunes at present exist precisely where they 
are found, should be classed as slightly older than the solian deposits first mentioned. 









Pelruleum— rontniued. 

Petroleum . . 


Theories regarding the Origin and 

Present Position of the Petroleum In- 

Mode of Ace u m u 1 a t i o n of 


dustry ill Taranaki 



History of the Petroleum Industry in 

(1.) Origin 




(2.) Mode of Accumulation 


(I.) Introductory 


Kvidcnee as to the Existence of Pay- 

(2. ) First Period u f A c t i v i t v ; 

able Oil-reservoirs in or near 

1865-C8 . . 


the Suljilivision 


(3.) Second Period of Activity: 1889 

(1.) Recapitulation of (Jeological 

to the Present Day 


Structure of the Subdivision 


(a.) 1889-1904 


(2.) Oil-seepages 


(6.) 1904 to the Present Day. . 


(3.) Analyses of Oil 


(i.) The Moturoa and Tara- 

(4.) Escapes of Natural Ga.s 


naki Petroleum Com- 

(5.) Analyses of Oas 




(6.) Conclusions 


(ii.) The Inglewood Oil- 

(7.) R^'commendations regarding 
Future Prospecting for Oil 

boring and Prosiwet- 

ingConii)aiiy (Limited) 


in Taranaki 


(iii.) The Moa Petroleum 

Iron-ores . . 


(Limited) .. 


(I.) Ironsand 


(iv.) The New Zealand 

(1.) Introductory 


Standard Oil Company 

(2.) Comjiosition of Ironsand 


(Limited) . . 


(3.) History of Attempts to treat 

(V.) The Taranaki Oil and 

the Ironsand 


Freehold Company (Li- 

(4.) Method and Results of 



Smiths Patent Smelting 

(vi.) The lionithon Frw- 



hold Petrok^um Com- 

l'<.) Remarks on the Economic 

pany (Limited) 


Possibilities of the Iron 

(vii.) The Xew Plymouth 

sand . . 


Petroleum Company 

(11.) Lnnonite 


(Limited) .. 


Mat^-rials for Roadmaking 


(4.) Comments on Pros|X'clint; 

Biiildini.' and IVitfery Materials 


Met hods 



He aruei) from the standpoint of economic gcolojiv. tlie New Plyuioutli Subdivision 
is int-eresting mainly in view of its possibiliticK as an oilfield, and to a minor ext«nt 
on account of its larj^e deposits of ironsai d. This chapter, therefore, deals mainly wnth 
these subjects. 


present position ok ihe petroleum indistry in taranaki. 

At the date of writinji (May. 1911) four oil-piospecting companies holdijig rights in 
or near the area under review are in existence. Of these, two (the Inglewood Company 
and the Taranaki Oil and Freehold Company) are not at present operating. The other 
two companies (the New Zealand Standard Oil and the Taranaki Petroleum Company) are 
engaged in boring. So far the Standard Oil Company of New Zealand has met with no 
pronounced success. The Taranaki Petroleum Company has two flowing wells yielding 
together about ll<) barrels per week,* and has more than six thousand barrels of crude oil 
stored in underground tanks. 

• A prospectus issued in April, 1912, gives the weekly yield from two wells, and a third (No. .5), 
as 360 barrels. 



(1.) Introdvctory. 

The presence of oil near the Sugar-loaves had been noted by the Maoris long before the 
arrival of Europeans, and was ascribed by them to the decomposition of the body of a sea- 
raonster. According to one of their legends, Seal Rock, now a reef, was once an island of 
bituminous matter, which was ignited and then burned below the sea-level. 

Dr. DiefEenbach* in 1839 noted the presence of oil near Moturoa, and also a " strong 
smell of sulphuretted hydrogen gas about a mile from high-water mark.'" 

In 186.5 the late Mr. E. M. Smith collected a .sample of oil, which he forwarded to 
the Birmingham Chemical Association, which institution gave a " splendid report on the 
character of the oil."t 

This accoimt of the attempts to obtain oil in Taranaki is divided into two sections, 
the first dealing mainly with the first period of prospecting activity, between 1865 and 
1868 : the second ^vith the renewal of interest in the venture between 1889 and the 
present day. In the second section the period of maximum activity and success (from about 
1904 to the present day) is separated from the earlier period. 

The sources from which this account has been compiled are very various. Special 
mention, however, should be made of the assistance received from a variety of docu- 
ments lent by Mrs. Fair and Mr. F. P. Corkill. 

(2.) First Period of Activity : 1865-68. 

The first attempt to reach the supposed oil-reservoir was made at the end of 1865. 
when Messrs. J. F. Carter, Ross, J. R. Scott, and J. Smith obtained from the Pro\Tncial 
Government the right to bore or sink for oil on 50 acres of land near the Sugar-loaves. It 
was stipulated that a royalty of from 3 to 7 per cent., according to the depth, should 
be paid on any oil obtained. The first oil-well in the district, which was afterwards 
known as the Alpha or " Oil or London " Well (1),J was sunk as a shaft for a depth of about 
60 ft. (which was reached on the 24th March, 1866), and continued by boring to a depth 
of about 180 ft. As will be seen by a study of the log contained on a separate sheet at the 
end of this report, " indications " were met with at various depths, the best being at 
60 ft., where occurred a seepage of thick greenish-brown petroleum, and at 180 ft., at which 
depth, according to Hector, oil to the amount of about 50 gallons a week was skimmed off 
the water. 

In order to develop these encouraging prospects a company known as the Taranaki 
Petroleum Company was formed about the end of 1866, with a capital of £10,000. This 
company also obtained from the Pro\'incial Government boring-rights over an area of about 
110 acres in the Sugar-loaf Reserve, immediately west of Carter and Company's lease ; also 
over the islands of Pararaki and (subject to special conditions) of Mikotahi, and " over all 
that land lying between said reserve and low-water mark." It was stipulated that the 
company should spend at least £3,000 at a minimum rate of £1,000 per annum in sinking 
for petroleum before the works were abandoned. 

The best j-ield obtained by the company from the Alpha Well was in Julv, 1867, when 
for a short period oil was pumped at the rate of 80 gallons a day. It is not clear, however, 
whether this oil came from the bottom of the well, or only from a depth of about 
90 ft., from which level, when the well was plugged at a depth of 110 ft., oil was 

* " Travels in New Zealand," vol. i, pp. 134, 135. 

t These facts are from a letter from Jlr. Smith to Mr. G. C. Fair, kin<lly lent to the \vTit«r bv Mrs. Fair. 

t These numbers are the index-numbers used to denote the wells on the geological maps'. A list of 
Taranaki oil-wells arranged in chronological order forms an appendix to this report, and a tabular comparison 
of the records of most of the wells forms a separate sheet from which details as to the levels of oil-flows &c. 
may be obtained. 


obtained at the rate of 8 gallons per day. It does not appear that the Taranaki Petroleum 
Company deepened the Alpha Well after purchasing it. 

About May or Jime, 1867, another bore, known as the Beta or " Oil or Edinburgh " 
Well (3), was begun by this company, from which, at a depth of 91 ft., 40 gallons of 
oil were obtained in ten or twelve houre. The yield, however, soon fell off to 3 or 
4 gallons per day. Little else of interest, save the losing of the tools at 510 ft., 
and the abandonment of the bore at 684 ft., is recorded concerning this well. 

The Taranaki Petroleum Company put down two other bores, known as No. 1 (4) and 
No. 2 (5), which reached depths of 310 ft. and 318 ft. respectively, apparently without 
encountering any hopeful indications. In addition to these bores, the company sank 
tw^o shafts to depths of about 60 ft. each. In the latter part of 1868, discouraged by 
the failure of the Beta Well, the Taranaki Petroleum Company was voluntarily wound up. 

While this company had been expending its capital on the sinking of four wells 
a smaller sjTidicate. k)iown as the People's Petroleum Company, with a capital of 
about £3,000, began operations at the end of April, 1866, on an area of about 
4 acres immediately east of Carter's claim, one of the conditions of the lease being 
that the company should spend at least £1,000 at the rate of £500 per annum in 
sinking for petroleum before the works were abandoned. A well, knowm as the 
Victoria or " Oil or Dublin " (2), was sunk to a depth of 516 ft. with apparently no 
tangible results. This practically ended the operations of the People's Petroleum 
Compaiw, which amalgamated with the Taranaki Petroleum Company, and with it was 
wound up towards the end of 1868. 

In June, 1866, Mr. (afterwards Sir Julius) Vogel began, it is said, to jtiit down 
as a private venture a bore on ground adjoining Carter's lease. At 17 ft. «nic(»uraging 
indications of gas and oil are reported to have been encountered, but no authentic 
account of these operations could be obtained by the writer. 

It is said that about the year 1880 two rSermans put down a coiij)!*' dl bores 
" near the Manganui River," but no further information regarding this venture is 

(3.) Second Period of Activity: 1889 to the I'lisent Dai/. 
(a.) 1889-1904. 

The second period of activity Ijegan in 1889. when, owing to the exertions of Mr. 
Oliver Samuel and Sir Julius Vogel. a company called the New Zealand Petroleum 
and Iron Syndicate (Limited) was formed in England. Plant was sent out from 
England, and an American driller (Booth) Wiis engaged. Mr. Charles Marvin, ti)c' well- 
known English oil expert, who had l>een appointed managing director, and was to have 
proceeded to New Plymouth to select the site of the bore and superintend drilling opera- 
tions, died when just about to leave for New Zealand. The loss of his advice no doubt 
had much to do with the half-hearted support which the enterprise received from the 
English directors. Messrs. F. P. Corkill and 0. Samuel were appointed local directors, 
Mr. CorkiU acting as general manager and attorney for the company in New Zealand. 

A site was selected at the base of the Breakwater (6), and drilling was begun bv 
Booth on the 8th January. 1891. Boring appears to have proceeded with expedition, 
and at a depth of about 915 ft. oil was obtained at the rate of about four barrels a day. 
Shortly after this the tools were lost in the bore, and many fruitless attempts were made 
to recover them, great inconvenience being caused by the lack of monetary' support accorded 
by the board of directors in England. Finally operations were abandoned owing to the 
want of funds, although the enterprise appeared to be on the threshold of success, 
and the driller (Booth) claimed to be able to pump 160 gallons of oil a day, and 
strongly recommended deepening the well by another 200 ft. On the 10th May, 1894, 


the property of the Petroleum and Iron Syndicate was sold in order to pav outstanding 
debts, and the plant was acquired by a syndicate of Taranaki and Sydney residents, 
referred to in this report as the Samuel Syndicate, by which a most determined effort to 
find payable supplies of oil was made. 

The services of a driller named Ludlow having been obtained, an attempt was made 
to iiopcMi Booth's well (6). which, from the quantity and variety of iron implements 
which it contained, would appear to have been intentionally blocked by some individual. 
Following this failure, R. E. Fair and two other drillers from Australia were employed 
to sink another well (7), about 8 ft. west of Booth's. After a number of mishaps, 
due to losing tools, &c., the hole was sunk to about 950 ft., when oil to the amount 
of two or three barrels a day was obtained. At 1,000 ft. a flow of aliout ten barrels 
a day was obtained. Much excitement was caused locally b>- this success, and many 
applications for shares were received, but Mr. Samuel, recognizing that the results 
liad been greatly exaggerated, obtained the subscription of further capital privately, 
so that the general public should not suffer in the event of failure. During this 
period of success the first consignment of crude petroleum from Taranaki was shipped 
to the Balclutha Water-gas Company, which continued for some time to be a regular 
customer. The Railway Department also for som_e years purchased crude petroleum for 
the manufacture of gas at its Petone works. Ultimately, owing to difficulties Avith 
the water which could not be overcome. No. 2 (7) was abandoned when at a depth 
of 1,100 ft. (or perhaps only 1,021ft.). It should be added that this well was cased 
to a depth of 885 ft., and, as in No. 1 (6), the water was foimd to rise and fall with 
the tides. 

No. 3 (8), or Mace's, or the Herekawe bore, was then put down on Mr. Mace's farm on 
the Herekawe Stream, close to the New Pljonouth - Omata Road, and was abandoned on 
the 26th October, 1895, after a depth of 1,534 ft. had been reached. Little oil was seen, but 
large quantities of gas were met with, and it is asserted that oil was seen flowing from the 
well after its abandonment. It is noted that in one part of the well sinking was much 
facilitated by the striking of a seam of quicksand, through which the casing sank by its own 
weight, so that the bore was sunk through this stratum at the rate of 10 ft. or 12 ft. in 
thirty minutes. 

No. 4 (9), or Samuel's bore (the No. 3 well of the present Taranaki Petroleum Company), 
was begun on the 11th November, 1895. At 908 ft. a large escape of gas was encountered, 
and at 910 ft. oil at the rate of ten barrels a day was obtained. Considerable difficulty was 
experienced in working the pump, which was frequently blocked by the mixture of fine mud 
lind oil. Shortly after this the flow suddenly cea.sed, most probably owing to the caAdng- 
n of the claystone which overlay the emptied oil-seam. Boring was therefore resumed, 
md " shows " of oil were encountered at various levels down to 1,976 ft. At this depth oil 
it the rate of eight barrels a day was for a short time obtained by pumping. Unfortunately, 
on the 22nd August, 1896, a fire, caused by the accidental ignition of the escaping gas, 
destroyed the derrick and .plant. Undaimted by this mishap, Mr. Samuel, who had assumed 
the direction of operations after the departure of Mr. Fair on the 29th February, 1896, pro- 
ceeded immediately with the erection of new plant. This work was completed by October. 
1896, and the water at 1,885 ft. having been shut off and a packer placed at 1,934 ft., oil 
unmixed wath water began to flow at the rate of 270 gallons per twenty-four hours. After 
H great many accidents to tools, casing, &c., the bore, in spite of the considerable quantity 
of oil which had been obtained from it, was finally closed down. 

The narrative of the Samuel Syndicate's doings may here be interrupted to note that 
in August, 1896, was issued the prospectus of the Egmont Petroleum and Mineral Boring 
Company (Limited), which held rights over an area extending from Barrett Road, across 
the Frankley, Carrington, and Mangorei Roads, and over another area in the Inglewood 


district. ' The total ;irea over wiiicii bormg-nghts were obtained by this concern was about 
5,000 acres. Owing, however, to the partial failure of the boring operations of the 
Samuel Syndicate, there was but small demand for shares, and the Egmont Petroleum Com- 
pany failed to materialize — a matter to be regretted, as in the writer's opinion the gromul 
formerly held by this company deserves closer examination than it has yet received. 
It may also be mentioned here that Mr. P. McColl, of Omata, is said to have drilled one or 
two holes to some depth with a very primitive apparatus about the year 1896. The approxi- 
mate situation of these works, no results of which arc available, is shown on the map (10). 

No. 5 (11), or Putt's bore, together with all the wells put down thereafter by the Samuel 
Syndicate, was sunk under Mr. Samuel's direction. It was situated about 100 yards south- 
west of No. 4, and reached a depth of 2,053 ft. during the early part of 1898, but. though 
several oil-bearing seams were cut, at no level could more than one barrel of oil per day be 

No. 6 (12), or Okey's bore, situated about four miles south of the Breakwater, was 
abandoned at a depth of 302 ft. owing to the great difficulty experienced in drilling through 
a coarse volcanic material. Often for days together not an inch of progress was made with 
the drilling. 

No. 7 (13), or Veale's bore, was situated near Okey's bore. Boring was begun in August, 
1898. and reached a depth of 1,220 ft. On the 2l8t February, 1899. the company, the Aus- 
tralian members of which had apparently become discouraged by the repeated failures to 
obtain oil, sold its rights and plant to Mr. L. W. Alexander, of New Plymouth. He in turn 
sold to a small syndicate of New Plj-mouth residents, of whom Mr. Samuel was the principnl 
shareholder. Under his superintendence No. 7 (13) bore was sunk by the new company to a 
depth of 1,335 ft. without any encouraging prospects, and was then abandoned. 

Undeterred by these repeated failures, Mr. Samuel then began No. 8 (14) bore. This 
bore was situated a few himdred yards south of No. 4 (9), which was still intermittently 
producing oil. As may be seen by a glance at the log of this bore, encouraging indica- 
tions were met with, the explosion of gas and oil marked as occurring at 1,730 ft. being 
sufficiently powerful to throw water and mud to the top of the derrick. Below 1,730 ft., 
however, no traces of oil were encountered, and when a depth of 2,052 ft. had been reached 
the casing was drawn and the bore abandoned. 

No. 9 (15) bore was situated close to No. 4 (9). Drilling was begun on the 10th 
December, 1900, and when the well had reached a depth of 1,080 ft. without result it was 

This ended the activity of the Samuel Syndicates. With the exception of No. 4 bore, 
their persistent efforts did not meet with success. The only positive conclusion to be drawn 
from the operations just detailed is that the main supply of oil is situated at a considerable 
depth, and that bores which do not ;tttain a depth of at least 2.0(H1 ft. below sea-level are of 
little value. 

(h.) 191(4 to the Present Day. 

During this period the prospects of the oil industry in Taranaki have become much 
brighter, and as a consequence several companies have been formed. In this section the 
doings of each company are separately outlined. 

(i.) The Moturoa and Taranaki Petroleum Companieji. — In 1904 operations took a fresh 
lease of life, when the rights and machinery of the company which put down the bores 
Nos. 8 (14) and (15) were sold to a syndicate largely financed in Adelaide. The late 
Mr. G. C. Fair was engaged as head driller, and on the 27th April, 1904, he began 
drilling the Birthday Well (16) a few hundred yards south of No. 4 (9). By January, 
1905, the well had reached a depth of 2,100 ft. at a cost of £1,800, without, so far as 
can be now ascertained, having encountered any very promising indications. At this stage 
3 — New Plymouth. 

• 34 

the Adelaide syndicate, being unable to find further capital, sold the plant and rights to 
a small company called the Moturoa Petroleum Company. This company had a capital 
of £2,000, and was formed in New Plymouth, chiefly through the exertions of Mr. G. C. 
Fair, who was very sanguine of the ultimate success of the project. With the aid of 
a Government subsidy of £1 per foot for 230 ft., the Moturoa Petroleum Company in- 
creased the depth of the Birthday Well to 2,230 ft., when, on the 22nd June, 1905, good 
oil was obtained, and the success of the company seemed assured. Difficulty, however, 
was experienced with the water, and it was decided to recase the well. This was a 
very difficult matter, because (owing to want of money) the original casing used was 
very defective. In order to obtain more capital the Moturoa Petroleum Company was 
merged into the present Taranaki Petroleum Company. This company has a capital of 
£120,000, of which £56,000 in fully-paid-up shares was allotted to the shareholders of 
the Moturoa Petroleum Company, and of the balance between 31,000 and 32,000 shares 
have been issued, on which 17s. 6d. per share has been paid up. By the 26th April, 
1906, the bore was recased and the water supposed to be shut ofi. The casing, however, 
is in a very bad state, being much bent, and ha\dng one or two holes punchtd right 
through it. The depth of the well was increased to 2,345 ft., and good oil was obtained from 
it. Eventually, owing to renewed difficulty with the water, the well was abandoned. 

In 1907 the company proceeded to clean out the bore, and during the year got down 
to a depth of 2,269 ft. Throughout 1908 and 1909 this work was temporarily abandoned, 
but in 1910 fresh efforts were made to clean out the well and insert 6 in. casing. This work 
was carried out to a depth of 2,320 ft. Operations have ceased at this bore for a time. It 
appears likely that in the same time and for the same money a fresh bore might have been 
put down alongside to a greater depth. 

In August, 1906, Mr. Fair began putting down the No. 2 (17), or Roy's well, situated 
between (16) and (9), but imfortrmately died before any great progress had been made. The 
sinking of the No. 2 well was continued imder the managership of Mr. W. A. Simpson, who 
was succeeded by Mr. L. Keith at the end of 1909, and under his direction the operations of 
the company are now proceeding. In the No. 2 (17) oil and gas were met with in small quan- 
tities at various depths, as much as two barrels of oil per day being obtained from one seam 
at a depth of 1,872 ft. During 1909 Mr. Berry, a former director and chairman of directors, 
urged that sinking should be continued, and, this ha\ang been done, at a depth of 2,209 ft. 
a considerable quantity of oil and very salt water was obtained. It is said that during a 
period of thirty-one days thirty-seven barrels of oil per day were obtained, but subsequently 
the yield decreased. Mr. Berry, who expressed himself as dissatisfied with the methods of 
management, undertook, subject to a penalty of £2 per day for failure, to obtain oil from 
the well at the rate of twenty barrels per day for twenty-four days. Mr. Berry did not suc- 
ceed in fulfilling his engagement, but nevertheless effected many improvements in the state 
of the well, and during an actual pumping-time of twelve days obtained 144 barrels of oil. 
Drilling was continued at this well until, at a depth of 3,030 ft., on the 5th January, 1910, 
a flow of oil at the rate of about ten barrels per day began and has continued steadily ever 
since. According to local report. No. 2 bore is not in a very satisfactory state, 250 ft. 
of casing being, it is asserted, adrift somewhere in the well. This bore, nevertheless, has 
80 far been the most successful in the district. 

Simultaneously with the drilling of No. 2 (17), the company began operations at two 
other wells, known as the No. 3 (9) and the No. 4 (18). The No. 4 (9) well of the Samuel 
Syndicate, being the third well to be worked on by the present company, is now known as 
the No. 3. Very great difficulty and expense were incurred in trying to clean and deepen 
this well, but ultimately success was attained. Boring has continued at intervals ever since, 
the most serious mishap being the burning-do wti of the derrick on the 6th or 7th Septem- 
ber, 1909. No. 3 well has now (May, 1911) a depth of 3,841ft., being more than 800 ft. 


further below sea-!evel than any other well in the district, and has produced since the 2nd 
March, 1910, oil at the rate of about eight barrels per day.* The progress of boring does not 
interfere with the escape of this oil, which conies to the surface between the 4 in. casing and 
the 5 in. casing, probably from depths of 2,800 ft. and 3,088 ft. Between .3,710 ft. and 
3,720 ft. great gas-pressure was encountered, blowing water and oil to a height of 70 ft. abov<- 
the derrick, and necessitating the cessation of work for some days. 

No. 4 (18) well of the Taranaki Petroleum Company was drilled simultaneously 
with the operations detailed above. It was situated a little south of No. 1 (16). 
reached a depth of 1,678 ft., and then, owing to difficulties with r|uirksand. was closed 
down, no decided indications of oil having been met with. 

No. o (25) bore, which is situated close to No. 1, but on the seaward side of the railwa^'- 
line, was apparently put down mainly with the object of retaining the rights over the ground 
on which it stands. Drilling appears to have gone on satisfactorily at this well, which is now 
(May, 1911) 1,745 ft. deep, and according to a Press message at the beginning of April of this 
year "two exceptionally \nolent blow-outs" at depths of 1,010ft. and 1,535ft. occurred. 
" The boring-tools were hurled out of the casing with terrific force, wrecking 200 ft. of steel 
cable. The debris was scattered for a quarter of a mile around, despite the fact that the 
derrick was roofed in."t 

Before concluding the account of the operations of the Taranaki Petroleum Company 
it may be noted that latterly the gas, which escapes in great quantity from bores 2 and 3, 
together with some waste oil, has been used almost exclusively for firing purposes, a con- 
•siderable sa\'ing in working-expenses being thus effected. 

For the purpose of bringing the potentialities of the industi}- before the public, a minia- 
ture refiner}' was erected at the works in 1910, and some hundreds of samples of the various 
products were distributed in and beyond the Dominion. 

With a view to attracting the attention of the Admiralty, which had decided to adopt 
the use of liquid fuel in the navj-, twenty-five barrels of crude oil during 1910 were presented 
t^ the authorities for test purposes. At the time of writing the results are not to hand. 

During 1910 also a hundred barrels of crude oil were purchased by the New Zealand 
Oovemment for the purpose of testing the comparative merits of oil and coal as steam - 
producers on the railways. It is understood the results were satisfactory'. 

Since writing the above it has been announced that as the result of a visit of inspection 
by Mr. J. D. Henry, editor of the Petroletnii Wnrld, the sale of the Taranaki Petroleum 
Company's property to a powerful British .syndicate has been arranged. 

(ii.) Th^ Inr/leivoud Oil-boring and Prospecting Company {Limited) was promoted 
in 1906 by a number of New Plymouth and Inglewood residents. The capital of the 
company was £10.000. in £10 shares, which were afterwards divided into £2 shares. 
Of this capital £6,655 was called up. The plant, which, with the derrick, cost £2,800, 
was purchased by the driller, Mr. A. D. McDonald, from the Oil Wells Supply Company 
in Pittsburg, and drilling was begun on the 9th September, 1907. on a site (23) close to the ~ 
railway-line and about three miles south of Inglewood. Drilling appears to have proceeded 
successfully, except that the water was never properly shut off. On the 13th August, 
1908, Mr. McDonald advised that, since the bore had reached ;i depth of 2,500 ft. 
without any decided indications of oil, further boring was not warranted and the well 
should be abandoned. Drilling therefore ceased after an expenditure of about £6,780 : 
but the greater part of the plant remains at the bore, and the company still holds 
boring-rights over 1,300 acres in the neighbourhood, and over a considerable area near 
the Mokau River. Negotiations concerning these rights are at present proceeding with 

* In February, 1912, the production of this w< U was rcportfil as forty barrels per week, 
t Towards the end of February, 1912, this well, at a depth of 2,323 feet, struck a flow ofoil estimated 
for the first day at 7'5 barrels. In April th"? flow tad lessened considerably, but was stUl satisfactory. 

3" -New Plymouth. 


Enfjlif.h capitiilists. Considering the depth at which good results had been obtained at 
Moturoa, the company might well have deepened the borehole by another 1,000 ft. 
before stopping active operations. 

(iii.) The Moa Petroleu7n (Limited). — A company known as the Moa Petroleum 
(Limited), the promoters of which appear to have been Wellington residents, began drill- 
ing operations close to the town of Inglewood (22) in August, 1907. The total number 
of shares issued by the company was 6,500, of which 1,500 were allotted as fully paid up. 
The total cash received by the company in respect of the contributing shares was 
£997 10s. The head driller was Mr. A. D. McDonald, who was also directing operations at 
the Inglewood Petroleum Company's bore, and was especially sent to Pittsburg by the 
two companies to obtain their plant. Apparently owing to lack of funds, the well was 
abandoned in January, 1908, when at a depth of about 460 ft. Two sets of boring-tools 
are reported to have been left at the bottom of this well. Promising indications are 
said to have been met with when the hole was between 200 ft. and 300 ft. deep, but, 
having regard to the experience of all other wells in the district, there is no doubt that 
much greater depths would have to be reached before any reliable information as to 
the value of the property could be obtained. At present the derrick, machinery, and 
tools are still in position. 

(iv.) The New Zealand Standard Oil Company {Limited), mostly financed, as the 
writer understands, by Auckland capital, began boring operations in December, 1907, on 
a site (24) near the Carrington Koad close to the southern boimdary of the subdivision, 
about five miles south of New Plymouth and within half-mile of the gas-vents on the 
Huatoki Kiver (see p. 43). Drilling has continued with fair regularity since, and 
the depth of the bore was stated to be somewhat over 3,200 ft. in the early part of 
1911. The company has a well equipped and maintained boring plant, and during 1910 
constructed a large concrete-lined reservoir for the reception of the expected oil. So 
far, however, nothing very tangible has been obtained. Recently the company has gone 
into voluntary liquidation, but it is understood that reconstruction is probable. 

(v.) The Taranaki Oil and Freehold Company (Limited). — This company was formed 
towards the end of 1906 for the purpose of purchasing and exploring for petroleum a 
10-acre block of freehold land in Vogeltown. one of the suburbs of New Plymouth. 
The capital was fixed at £15,000, in £1 shares, of which 13,500 have been allotted. The 
direction of the drilling operations was put in the hands of Mr. W. Balloch, who had 
had long experience in well-boring, including a period spent in the oilfields of South 
Russia. Drilling was begun in June, 1907, and continued for over two years, progress 
being slower than had been anticipated, owing, it is said, to the difficult nature of the 
country encoimtered, to the large diameter of the bore, and to various mishaps. The 
first signs of oil were met with at 450 ft., and " shows " were got at various depths 
down to 975 ft., where a so-called petroliferous sand was met with which is reported 
to have yielded oil at the rate of four barrels per twenty-four hours. Indications from 
this point downwards continued, it is said, to be most encouraging, more especially 
between 1,160 ft. and 1,200 ft. At 1,385 ft. boring was discontinued for want of funds, 
and, although the directors are confident that capital enough could be raised locally to 
continue operations for a time, they are, the writer has been given to understand, 
endeavouring to secure the interest of large capitalists. The works have been standing 
idle since about December, 1909, but are kept in good order. 

(vi.) The Bonithon Freehold Petroleum Company (Limited) was registered on the 25th 
July, 1905, with a nominal capital of £25,000, in £5 shares, for the purpose of obtaining 
an oil-boring plant, and purchasing and exploring for oil a freehold property known as 
" Bonithon," situated between New Plymouth and the Breakwater. There was never, 
apparently, a very keen demand for shares in the company, and a large amount of the 


mouey received in the form of calls had to be credited to the vendoi's in reduction of 
their claim of £5,250 for the balance of the purchase-money. A bore was sunk by con- 
tract to a depth of 3,000 ft., and, though encouraging indications are said to have been 
obtained, oil in any quantity was not met with. At length, on the 1st December, 1908, 
the available capital being exhausted, it was resolved to wind up the company. 

At present, the writer- understands, there is a proposal afoot to form a company, to 
be known as the Bonithon Freehold Petroleum Extended Company (Limited), to take over 
the assets of the former company and to sink the present bore an additional 500 ft. or 
until oil is struck. These proposals are embodied in a glowing prospectus, the authorship 
of which appears to be a secret. 

(vii.) The New Plymouth Petroleum Vomfany {Limited) was formed earlv in 1907 
with a capital of £10,000, in 2,000 £5 shares, of which 100 shares in addition to a sum 
of £2,500 were allotted to the vendors for their boring options. 1,500 fullv-paid-up 
shares, the majority of which were taken up in Dunedin, the headquarters of the com- 
pany, were offered to the public. Drilling under the direction of Mr. H. E. Bunger, from 
California, was begun near Omata (19) in March, 1907, and ceased in November of the 
same year owing to lack of funds, when the bore had reached a depth of 1,060 ft. 
The abandonment of this bore at such an inconclusive depth is much to be regretted. 
Quite apart from the fact that the tools are said to have frequently come up dripping 
with oil at the 1,060 ft. level, the neighbourhood of this bore is one which in the writer's 
opinion deserves thorough prospecting by means of holes of an adequate depth. 

(-1.) C'omiHcnta on ProsptctiiKj Methods. 
The importance and extent of the Taranaki oiltield still remain to be proved. Con- 
sidering the time and money which have been spent in oil-prospecting in the district, the 
amount of evidence for or against the existence, in the area under discussion, of the 
large oilfield in which so many people firmly believe is small. The following are the 
most obvious reasons for this disappointing result : — 

(a.) The crowding of bores in the neighbourhood of the Breakwater. This 
crowding policy, which would be understandable in an established oilfield, 
seems inexplicable in the case of avowed prospecting companies. 
(b.) The abandonment of bores at insufficient depths, 
(c.) The total absence in some cases, and the fragmentary character in most 

others, of records of the strata passed through in the bores. 
(d.) The total absence in most cases, and the fragnxentary character in almost 

every other, of samples of the strata passed through in the bores, 
(e.) Inaccuracy in recording depths from which saniples are obtained. Many 
cases have come under the writer's notice of samples being definitely 
labelled as coming from a certain depth when from a comparison with 
neighbouring bores it is certain that the rocks in question had fallen in 
from above. 
(/.) In the case of logs unaccompanied by actual samples, the great inaccuracy 

and inadequacy of the descriptive terms employed. 
(g.) C4eneraliy the absence of the most modern methods, and of expert advice 
and supervnsion. Companies now operating have made some improvement 
in these matters, but much yet remains to be done. 


(1.) Origm. 
Theories regarding the origin of petroleum, natural gas, and allied substances may be 
divided into two clnsses. According to the " inorganic theory," oil and gas were formed 


!))• water coming in contact at great depths with highly heated carbides of iron, man- 
ganese, and other metals. Upholders of the " organic theory " maintain that the vast 
majority, if not all, of the petrolaceous products have been formed by the alteration of 
organic remains entombed in sedimentary rocks. As to whether this alteration is due 
to slow distillation combined with bacterial action taking place at low temperatures, or 
to distillation at higher temperatures due either to the deep _ burying of the remains in 
question or to the action of intruded igneous rocks, there is not as yet universal agree- 
ment among the upholders of the " organic theory." 

The evidence favouring the "' organic theory " is almost overwhelming, and recent 
investigations indicate that slow distillation at low temperatures is the more probable of 
the two views as to the means by which the organic matter was altered. 

(2.) Mode of Accumulation. 

The most widely accepted explanation of the mode of accumulation of petroleum is that 
known as the " anticlinal theory.'" Petroliferous strata commonly consist of more or less 
rapidly alternating beds of sand and cla}\ It is generally believed that the petrolaceous 
substances were originally formed in the shales, and afterwards slowly made their way into 
the overlying more sandy layers, from which their escape directly upward was prevented 
by overlying beds of more clayey material. The petrolaceous products, being of less specific 
gravity than the water contained in the strata, would tend to flow upwards along the under- 
surface of the impervious clay beds, and would thus tend to accumulate along the crests of 
anticlines. According to this theory, then, the most favourable sites for bores are along the 
anticlines of the petroliferous series. The anticlinal theory of oil-accunmlation has been 
very largely corroborated by actual experience in many petroliferous districts. 


(l.) Recapitulation of Geological Structure of the Subdivisiori . 

As the reader will have observed from statements on former pages (see especiallv 
pp. 12, 16, and 25) the petroliferous strata of the New Plymouth Subdivision — i.e., the Onairo 
Series — are overlain by the accumulations of volcanic debris called in this report the Pouakai 
Series. As a rule, the Pouakai Series is miconformable to the Onairo Series, but it seems 
probable that no great lapse of time separates the two series, and that in some places they 
are actually conformable. If this be the case, the inclination of the Pouakai beds should form 
a key to that of the Onairo Series when the latter cannot itself be seen. The Pouakai beds, 
however, are nearly always horizontal. Either, therefore, the petroliferous Onairo Series 
is horizontally bedded in the western portion of the subdivision, or no clue as to its arrange- 
ment is obtainable. In the more eastern portion of the subdivision it has been shown that 
there is some evidence that the Onairo rocks form the western end of an easterly-pitching 
anticlinorium, the axis of the anticHnorium running in an east-south-east direction through 
the southern portion of the Waitara Survey District. The unconformities, in the Onairo 
Series itself, recorded by previous observers, would possibly be planes along which 
the ascending petroliferous substances would make their way to the surface. The writer, 
however, has been unable to find any evidence of such unconformities. The conclusion 
arrived at, therefore, is that the geological structure of the subdivision, so far as it lias been 
possible to decipher it, affords no indication as to the distribution of oil-reservoirs. 

It is possible, however, that the distribution of oil-seepages and gas-escapes may ofEer 
some clue as to the position of petroleum-reservoirs. It is proposed, therefore, to state on 
the fol!o\\ing pages what is known as to the distribution of surface indications in and near 
the subdivision. 


(2.) Oil-seefoges. 

The only undoubted occurrences of petroleum at the surface within the subdivision are 
the seepages which occur on the sea-bottom near the Breakwater at New Plymouth. On 
calm days the sea is often covered for a considerable distance with a film of oil. At the 
present time the dredge at work inside the Breakwater brings up a sufficient quantity of oil 
mixed with the debris to preserve the machinery from rust. A large number of reported 
oil-seepages were examined by the writer, but the great majority proved to be merely scums 
of iron-oxide formed by the oxidation of ferrous carbonate. In other cases this scum was 
found to be organic in origin, and due either to abundant fresh-water algae, or to the decom- 
position of animal or vegetable matter. 

The following reported oil-seepages deserve more detailed description : — 

(1.) In the creek about half a mile south of Trig. Station D (Elliot), in Westowu. 
near New Plymouth, oil is said to have been seen floating on the water. Nothing of any 
moment was observed on the occasion of the writer's visit. 

(2.) About 20 chains east of the mouth of Waireka Creek a decided smell of oil* was 
noticed by the writer whenever he visited the place. There is probably an oil-seepage 
amongst the coarse boulders which lie along the base of the low clitt'. 

(3.) On the Sugar-loaf Motumahanga a smell of oil was noted by the writer in 
February, 1910. 

(4.) During the summer of 1910-11 an escape of oil (and of gas) in the Waiwakaiho 
River, between the railway and traffic bridges, was reported in the local papers. The 
writer visited the locality several times, but was unable to detect any trace of oil, although 
the exact locality was indicated by the discoverer, Mr. A. E. Watkins. 

(5.) In April, 1911, according to Press Association telegrams, 'splendid indications" 
of oil were found in freshly dug post-holes on Mr. Henr}' Weston's farm on Frankley Road. 
The writer understands, however, that the report was exaggerated. 

(6.) In a letter to the writer in April. 1911, Mr. R. W. Davies, of Westown, mentioned 
finding, when working at a dipth of about 5 ft. in a new drain, a good " show of oil " about 
8 chains from the New Plymouth Oil and Freehold Company's bore. The writer has had 
no opportunity of visiting either of the last two seepages. 

(7.) In early days, befoie the existence of any commercial midertakings which might 
have given rise to the phenomenon, large patches of oil are said to have frequently been 
noticed floating on the sea at the mouth of the Waitara River. It is possible that the oil 
had drifted from the Sugai-loaves near New Plymouth, where, as mentioned above, films 
of petroleum are still frequently seen extending over ( onsiderable areas. 

(8.) Near the junction of the Devon and Richmond Roads, just west of Waitara, oil is 
said to have been seeii oozing out of a bank and flowing into a small stream. Many other 
oil-seepages are reported from this neighbourhood. All seen by the writer were scums of 

(9.) Thirty-five years ago strong traces of oil are said to have been found by Messrs. 
Vickery and Hicks when digging a sheep dip near the old military settlement of Tikorangi. 
Almost the exact location of the sheep-dip was indicated to the wTiter by Mr. Hicks, and two 
holes were dug to what he considered the depth at which tht* oil had oozed c)ut in former 
days, but no trace of petroleum was observed. 

(10.) Close to the farmhouse at the jimction of the Kelly and Ackworth Roads petroleum 
is said to be found as a scum on the surface of the water of a small spring, especially after 
heavy rains. The owner of the property asserted that this scum had more than once been 

. * It should be noted that in this and the following case where the smell of oil is noted the direction of 
the wind precluded the possibility of the smell having come from the Taranaki Petroleum Company's bores 
at Moturoa. 


collected hiuI Ijunil by means of a small wick. Samples of the scum taken by the wrriter 
contained nothing but iron-oxide. 

(11.) At Inglewood, between the Moa bore (22) and the Mountain Road, which runs 
alongside the railway-hne, there are numerous occurrences of iridescent scum in a piece of 
swampy ground, and a smell of petroleum has also been occasionally detected. A sample 
of the scum, however, was found by^^'tte^ Dominion" Analyst to contain no petroleum. 
A similar scum seen oji the same property near the Wortley Road proved to be iron-oxide. 

(12.) On the Bristol Road, near its junction with Junction Road, a good show of oil is 
said to have been seen during the summei of 1909-10. When examined by the \mter in the 
summer of 1910-11 the scum was evidently iron-oxide. 

(13.) Seepages of oil are said to occur near the Manganui Stream, on the southern 
boundary of the subdivision at the junction of Bristol and Everett Roads, and again on the 
left bank of the Mauganui Stream. These seepages appear to be merely iron-oxide. 

(14.) A great number of wells in various parts of the subdivision are said to yield water 
with a flavour of kerosene. So far as the writer had an opportunity of judging, the unpleasant 
taste is due to excess either of iron-oxide or of organic acids in the water. 

(15.) Just south of the southern boundary of the subdivision, on a farm on the north 
side of Kent Road, about half a mile beyond the junction of Kent and Junction Roads, 
during the smnmer of 1907 a sample was obtained which was analysed by a druggist in New 
Plymouth and found to contain oil. At present the very smallest traces of what is possibly oil 
are occasionally found, but on the occasion of the writer's visits the quantity was too small 
for any conclusive tests. 

(3.) Analyses of Oil. 

The crude petroleum which is at present being obtained from the Taranaki Petroleum 
Company's No. 2 and No. 3 bores (17 and 9) is at ordinary temperatures a thick viscous fluid, 
green by reflected and reddish-brown by transmitted light. The oil is mixed with saline 
water. Water from No. 2 bore, after separation from the oil by settling, was collected 
during the summer of 1909-10, and yielded the following analysis (results expressed in parts 
per 100,000) :— 

Sodium-iodide . . . . . . . . . . . . 2-0 

Potassium -chloride 







Ferrous bicarbonate 





Dr. Maclaurin remarks, " This is a muriated saline water containing about 25 per 
cent, more salts than ordinary sea-water. It differs from sea-water mainly in containing 
very much more calcium-bicarbonate and practically no sulphates. It contains a con- 
siderable amount of iodine, and in general composition resembles some of the Kreuznach 
(Rhenish Prussia) brine springs, which are reputed to have considerable medicinal value." 

The oil, after separation from the water, usually solidifies at about 69° Fahr., but 
the melting-point varies somewhat. The specific gravity is given by Pond as 0-832 
at 80° Fahr., by Easterfield as 0-84 at 65° Fahr., by Skey as 0-8275 at 60° Fahr. 
According to an anonymous writer,* the crude oil ignites at 260° Fahr., and boils at 
340° Fahr. Skey states that the flashing-point and boiling-point are 106° and 230° Fahr. 
respectively - 

The following are analyses of Taranaki oil from various localities, together with an 
analysis of oil from Waitangi Hill (Gisborne) and one of oil from Kotuku (Westlaod) : — 

♦ Mining Journal, 18th June, 1910. 



Si •* 

■ >o -* 
• t- 00 

d d 

O • - 

OS • • 


•jusQ jaj 








60-3 0-9002 

00-0 . . 

iuao a.),[ 

<N lO O 

d d di 


o J3 


~ Ol 



tj o o 

^ m 

g ^ .^. 


£ OCT 



r® -^ .. ■^ - 

« . 

!^ ic >^aq "5 
^co -Q ^ -^ 


3 a 


3 >-' 

_^ Ph ar; ^ ~ 


^tCg,^ . 



"2 "^ "3 ■ >. 

^ C5 =S t; CS 

-g-' gp2Q 
<4^ di— >^ 




S Tl 



■JU30 J3<T 




lO p c 

05 i6 d 


o >a 



5 S 



- ju»3 joj 




»— 4 





O O 


o o 






















— . 













I ^ 

I o 


s « 
— 33 

05 ^ ^ — ' ^ kV 

' a c^ ^ *^ 

.^ « g J § r^ 
_- ^ S !^ '^ 

^-^ - ^ ^ = 

+3 — IS in 2 

s r 2 o J 

CO r- _> -H CS 

O 5 r^- „, > 



■j: -5 .3 

i^ g . 3 =^ ^ 


CO >^ 

d ^ 
si E 
i^i .^ 



•0 o9-ei I* 



-.* CO 

• t~ 00 

d d 
! in t-- 








ofi-ei ■»« 











15-0 0-799 
42-0 0-841 


■%uao Md 

CO p p 

CO in CO 




■XUaQ jdj 


• t^ 00 


50° C. 20-0 
>tween 1 40-0 


o o p 

CO CSl '^ 

1— 1 





O tt 


3 CO ■* 

= a^ 

^3 ■*^ S^ T: 

-3 — • .tc P 3 

_,- ^3 O »-r-< <^ ^ 
3 CO o 

. = ■-5 8 — ■ - 

2 -— T-! *"• 

'-a ■© 3 .3 

^o3 3^33--0 

^ CO CD _3 Qu Ou J 



30 i. 

3} o; 







=e J:- 

53 >, 





>- ^ 
















3 ^"^ 


3 . 




a) . 

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*^ ^ 



+5 Ci 

-*^ OS 




C^ 1-H 

^ 1-^ 


C-< . 




: ^ 




■^ ^ 

-i &. 






03 , 



c3 ■•« 




H >• 







"* 3 




^ • — 


• r- 1 








'I l^'l 






The two analyses subjoined may be of interest. 

(1.) Apparently from Booth's well (6). (Boverton Redwood, July, 1891*):- 

Petroieum spirit ""'"^ '^"'- «G-* ««' ^^ 

Petroleum oil (kerosene) . . 

Intermediate and heavy oils with solid hydrocarbons 

Coke and loss 





, Spirit 
Kerosene, first quality 
Kerosene, second quality 
Spindle -oil 
Refined wax 
Residue oil from wax 


of i„lts,'°"°™* """' "' "■' *"""'°° "' °" ''"•^ "" ""^" -"'-" -oy be 
1866*) :i"°" ''"'" "'" " ^"S"-'"""'" (New Zealand Government Oazem. 2<Jth June. 

Per Cent. 

Sp. Gr. 



. . 14-31 


. . 32-00 


79<^ Fahr. 

. . 6-25 


76° Fahr. 

. . 14-81 








. . 10-70 

. . 1-80 



Sp. Gr. 

Per Cent. 


. . 0-874 



. . 0-893 



.. 0-917 


Solid bitumen 

. . 0-941 


Fixed carbon 




Specific gravity of crude oi 

1, 0-962. 


(2.) W. Skey (Trans., 

vol. vi, 1874, p. 252). " Oil 


Sugar-loaves " 



ume of Distillatt 
upon Charge. 

sp. Gr. 


Per Cent. 




















. 12-0 






. 13-0 





' ' 




• See alsn " 


« «„J Ji- T- 




Experts seem to agree regarding the excellent quality of the products which may 
be obtained from Taranaki oil. Redwood remarks that the kerosene distillate is of such 
satisfactory colour and odour as it comes from the still that it hardly requires the 
customary treatment with acid and alkali. He regards it as probable that a larger 
sample of crude oil than that submitted to him would yield 6 or 7 per cent, of solid 
hydrocarbons. A. F. Craig and Co. speak in similar terms of the sample examined 
by them, and add that in character and purity the crude oil resembles Penusylvaniau 
petroleum. The kerosene, however, shows a tendency to smoke in American lamps. 
The oil is found to be of a more complex character than that obtained at the Waitangi 
Oil-spiing, Povert)' Bay district,* since it contains 20 per cent, of benzene, whicii is 
not represented in the latter. This, however, is surface oil from which the lighter 
hydrocarbons have evaporated. The percentage of lubricating-oil in Taranaki petroleum 
is much lower, while the percentage of paraffin is much higher, than in Poverty Bay oil. 

From trials with locomotives conducted on the New Zealand railways there seems 
no doubt that the crude oil produced at the Taranaki Petroleum Company's No. 2 and 
No. 3 wells forms an admirable fuel for steam-raising purposes. 

(4.) Escapes of Natural Cfa-s. 

A considerable number of gas-vents occur in and near the New Plymouth Subdivision. 
The most important may be described as follows:— 

(1.) Gas escapes under strong pressure from bores Nos. 2 and 3 (17 and 9 on the 
map of the Paritutu Survey District) of the Taranaki Petroleum Company, and is 
used in the furnaces of the company, a considerable saving in fuel being thereby 
effected. Analyses of the gas from these two wells will be found in the next section. 
The gas from No. 2 escapes from depths of 2,250 ft., 2,560 ft., 2,800 ft., and 3,000 ft. 
In No. 3 the principal escapes are from the 2,676 ft., 2,600 ft., 3,710 ft., and 3,720 ft. 
levels. In March, 1911, gas was struck in such great volume at 1,010 ft. and 1,535 ft. 
in the Taranaki Petroleum Company's No. 5 bore as to " force the silt over the top 
of the derrick," according to telegrams in the daily papers. 

(2.) Numerous escapes are situated on the Huatoki River, near and south of the 
southern boundary of the subdivision. These vents have been known for nmnv years, 
and. so far as can be ascertained, have continuously discharged large quantities of 
gas. Tlie vents in this neighbourhood are thus described by Bellf : " On the property 
of Mr. A. 8. Petch, a number of gas-emanations appear on a small creek, a tributary 
of the Huatoki. Two ( about 1 chain apart) are especially conspicuous. The upper issues 
on the edge of the stream on the left side, while the other bubbles forth in a small 
pool of water tilling an artificial excavation. When lighted both burn vigorously 
for a few minutes, with almost a foot of flame of a yellowish colour. When first 
discovered and somewhat opened out, the upper jet of gas is said to have burned 
continuously for ten days. Further ebullitions of gas on a smaller scale appear 
on the Huatoki, above and below the entrance of the small stream above mentioned. 
Much of the surface soil of this locality is composed of a curious resin-coloured 
peat(?). but I am not of the opinion that such strong flows of gas could be derived 
from this source. They are probably of more deep-seated origin. About three-quarters 
of a mile lower down the Huatoki Valley, on a tributary entering on the right side, 
other jets of gas appear like those on Petch's farm, and apparently almost equally 
strong. Here some advantage has been taken of the gas, a roughly made cone being 
placed over the vent to concentrate the gas and give a constant flame when necessary 

• See Bulk-till No. 9 (New Series), N.Z.G.S.. pp. 37 and 38. 

t '■ rrelimijiary Reriort on the Taranaki Oilfield," C.-14, 1909, p. 3. 


for boiliug water, &c., by the men working in the neighbouring fields. Still lowea' 
down the Huatoki Valley, about half [a^milej from the right bank of its tributary known 
locally as the Huatokiti, andjon the property of Mr. Grooby, Frankley Road, there 
is a very strong ebullition of gas issuing on the edge of a tiny puddle of water in 
an artificial excavation in tufa. The jets flow from several small cracks occurring 
in an area of about 18 in. square, giving when lighted a strong flame 18 in. or 2 ft. 
m length, which burns without cessation unless somewhat violently extinguished." An 
analysis of a sample of this gas will bo found in the next section. 

(3.) In the neighbourhood of the Moa Petroleum Company's bore at Inglewood 
(22 on general map) gas is constantly escaping from a hole dug in a peaty "deposit 
of recent geological age. A sample of this gas was analysed, with the result given 
below. Small escapes of inflammable gas are said to be common at Inglewood. 

(4.) On Mr. Bishop's farm near the right bank of the Mangaone Stream, nearly 
two miles above its junction with the Waitara River, a considerable and continuous 
escape of gas occurs in a small swampy stream. The rocks through which the escape 
is taking place are the volcanic debris of the Pouakai Series. An analysis of this gas 
is given in the next section. 

(5.) Gas is escaping at the head of a runnel on the left bank of the Mangaone 
Stream about a mile south of the southern boundary of the subdivision. From the 
close proximity of the claystones of the Onairo Series it is almost certain that this 
gas, an analysis of which will be found in the next section, is escaping through them ; 
but in the hole whicli was dug to facilitate the collection of the gas the chief material 
obtained was volcanic grit, some of which was very ptmiiceous. 

(6.) Strong escapes occur south of the southern boundary of the subdivision and 
about two miles due south of Junction Road on the Mangamauhete Stream, a tributary 
of the Manganui River, for a distance of some chains along the left bank and in the bed 
of the stream itself through bleached volcanic sand. An analysis of this gas is quoted 

(7.) About 5 chains from the Inglewood Petroleum Company's bore (23 on general 
map) on the Norfolk Road, about three miles south of Inglewood, a fairly strong escape 
of gas (an analysis of which is given below) is taking place by the side of a small stream. 

The following less weU-authenticated or smaller escapes of gas in and near the sub- 
division deserve some notice : — 

(i.) The reported oil-seepage and gas-escape on the Waiwakaiho River just below the 
railway-bridge has been dealt with in a preceding section (p. 39). 

(ii.) Small gas-escapes are fairly common in the small streams in the neighbourhood 
of the Taranaki Oil and Freehold Company's bore (20 on map of Paritutu Survey Dis- 
tnct). Some of these escapes are possibly of deep-seated origin, but the majoritv no 
doubt result from the decomposition of superficial deposits of organic debris. 

(iii.) in 1906 or 1907, on Mr. W. Davies's farm (Section 11), on the Waitangia 
Creek, near the dairy factory on the Junction Road, a little south-east of the junction 
of the Mangorei and Waiwakaiho rivers, some prospectors are reported to have obtained 
gas, and a distinct smell of petroleum by boring to a depth of 25 ft. On the strength 
of these indications the property is said to have been sold at a price considerably above 
its value as agncultural land. No such indications are now visible. 

(iv.) On a branch of the Waitangia Creek, where it crosses and is damned up by the 
Junction Road near the last-named place, a few bubbles of gas and also much dark- 
brown scum are usuaUy to be seen. Probably these "indications" are of no import- 



(v.) On ^[r. Hosking's farm (Section 109), on the Te Arei Road, near the Sentry 
Hill flour-mill, gas is said to have been observed escaping in some volume during the 
dry weather of 1907. The writer could see none in the summer of 1910-11. 

(vi.) Escapes of gas are reported to have been observed close to the brickworks ne;ir 
the Devon Road about a r|uarter of a mile on the New Plymouth side of Wait;ira. The 
writer lias been unable to satisfy himself as to this occurrence. 

(vii.) Gas. the composition of which is unknown, continuously escapes in small 
quantities from the artesian wells in Messrs. Borthwick and Son's freezing-works at 

(viii.) (Tas is said to escape at a point on the big bend of the Waitara i^ivrr jnst 
above the settlement of Huirangi. This occurrence could not be found by the writer. 

(ix.) Near Lepperton. on Section 10, on the Manutahi Road, and about a quarter 
of a mile west of the railway-hne, there is said to have been a strong escape of gas in a 
well about 50 ft. deep, sunk in the volcanic debris of the Pouakai Series. At the time 
of the sinking of this well, twenty-five years ago. a man is reported to have been injured 
by an explosioji due t-o the ignition of the gas. 

(x.) A similar accident occurred during February or March of 1908 to a man 
engaged in sinking a well on Mr. F. W. Cornwall's property (Section 85) on the Corbett 
Road, about one mile and a half north-west of the last-named locality. Tbi- w<>11 wns 
at a depth of about 50 ft. when the explosion occurred. 

(xi.) As already mentioned (pp. 27, 43), the gas-escapes described under (2) above arc 
accompanied by a somewhat remarkable peaty deposit, analyses of which are i|uoted. 
Mounds of a verv similar deposit were noted in the following places, and nuiy 
be regarded as affording some evidence that they are the sites of former gas- 
vents. In Mangarewa Creek, on Sections 122 and 109, about 30 chains .south of Trig. 
Station XXII. two mounds about 3 ft. high occur. It is said that in this plac, when 
the stream was liigh, gas was seen escaping from under the water and was lit. On tlie, 
Upper Puketotara Creek, on Mr. H. Hall's farm, near the boundary of Section 130, and 
about half a mile south of Trig. Station XXI, a similar mound over half a chain in 
diameter occurs. 

(xii.) On the Waitara River for some distance above the mouth of the MangaoiK^ 
Stream numerotis gas-escapes, apparently too constant to have -i mere superficial origin, 
were noted. 

(xiii.) Bv the side <if the Mangaone Stream, aliout 20 chains south of the large 
escape described above (No. 5), a rather diffuse and feeble gas-escape o( t urs through 
swampy ground. 

(xiv.) A ■■ mud volcano." the site of which was approximately half a mile .south of 
•Junction Road, where the Norfolk and Suffolk Roads now join, near the Manganui 
River, was noted in 1873 by Mr. C. W. Hursthouse when carrying out a surve)'. The 
Maoris told him that in 1859 a big outbreak, the noise of which could be heard at the 
pa on the other side of the Manganui River, threw mud over the trees for some 
distanre. This occurrence was regarded by the Maoris as an omen of some important 
event — a belief confirmed by the outbreak of the Taranaki war in I860. 

(xv.) On the Bristol Road, a few chains north-east of its junction with Junction 
Road, in the same stream in which an oil-seepage is .said to occur (see (12), p. 10) a 
strong escape of gas was reported during the summer of 1909-10. When the place 
was examinetl by the writer during the summer of 1910-11 only a few bubbles of gas 
were seen. 


The following are 
near the subdivision, 
corked, with a little 
inverted |)osition. and 

(5.) Analyses of Gas. 
analyses of the natural gas from the most important vents in and 
In every case the gas was collected in clean bottles, which were 
water inside as an additional precaution, sealed, packed in an 
sent without delay to the Dominion Laboratory in Wellington. 









Methane (CH^ ) 






95- 10 



Ethane (C^Uf.) 



Olefines (C„PL.„) . . 









Carbon-dioxid'e (COj) 









Oxygen (0) 









Nitrogen (N) 










100-00 100-00 100-00 100-00 100-00 100-00 100-00 100-00 

Localities — 

(1.) No. 2 bore, Taranaki Petroleum Company (17 on map). 

(2.) No. 3 bore, Taranaki Petroleum Company (9 on map). 

(3.) Petch's farm, near Carrington Road. 

(4.) Bishop's farm, Maugaone Road. 

(5.) Section 24, Mangaone Road. 

(6.) Near Moa Petroleum Company's bore (22 on map). 

(7.) Near Liglewood Petroleum Company's bore (23 on map). 

(8.) Maungamauhete Stream. 

For the sake of comparison the following analyses of natural gas from other parts 
of the world may be quoted.* 

Hydrogen . . 
Marsh-gas . . 
Olefiant gas 
Carbonic oxide 
Sulphuretted hydrogen 

, ,. . 100-00 99-98 100-00 

Localities — 

(1.) Ohio (Fmdlay). 

(2.) Russia (Caspian Region). 

(3.) Pennsylvania (Lyon's Run, Murraysville). 

It would thus appear that samples 3 to 8 have a composition agreeing with that of 
natural gas from other parts of the world. Samples 1 and 2. on the other hand, differ 
markedly in their very high carbon-dioxide content from any gas-analyses quoted by 
Redwood. The large quantities of carbon -dioxide in the gas" from the bores at New 
Plymouth are probably due to the hydrocarbons becoming mixed with carbon -dioxide 
evolved as a last phase of the volcanic acti^^ty which was at one time rife in the neigh- 

(6.) Conclusions. 
After a study of the very imperfectly revealed geological structure of the subdmsion t 
and after a careful comparison of the generally unsatisfactory bore-records, the writer has 
come to the following conclusions : — 

1. The chief oil- and gas-producing strata of the area are the rocks of the Onairo 
Senes, which is Miocene in age. 







93-07 ' 


3-26 1 













t Sril^Stsl";'! it^''°>"°*'-" '')' ^" ^^''':;*°" ^-1^^'°°^. and edition, vol. i, pp. 24^250. 
T ilie dotailod results of the writer s geological studies are set forth in Chapter II. 


2. The gas which is found escaping in considerable quantitv from the rocks of the 
overljang Pouakai series, and the oil of which a few undoubted seepages from the same 
rocks occur, originated mainly or wholly in the Onairo rocks. 

3. There is no evidence as to the mode of origin of the gas and oil. 

4. No distinct anticlines and synclines can be distinguished in the rocks of either 
the Onairo or the Pouakai Series, nor are there any geological data which justify the 
selection of bore-sites. 

5. Petrolaceous substances probably exist at or near the surface in the country to 
the east of the New Plymouth Subdi\asion.* 

6. The rocks in which these petrolaceous substances e.\ist conformably underlie the 
Miocene rocks, which are exposed in the subdivision and are probably over 5.000 ft. 
below the surface of the neighbourhood of New Plymouth. 

7. Oil has been found in payable quantities on the Taranaki Petroleum C!ompajiy's 

8. The oil horizons as disclosed by boring near New Plymouth lie at approximately 
1,000 ft., 2,000 ft., and 3,000 ft. below sea-level, but owing to the variable character of 
the strata are ill-defined, and are at var\ang distances from the surface in neighbouring 

9. The 3,000 ft. horizon is the most productive. 

10. The 1,000 ft. horizon is probably of least importance, but merit* more careful 
prospecting than it has yet had. especially near Booth's well (6). 

11. The position of oil -reservoirs in the subdivision can be determined only by 
systematic deep boring. 

12. A belt of country about three miles wide in which gas-vents oit ui extends 
from the Sugar-loaves in an east-south-east direction for at least fifteen miles. 

(7.) RecomiiKiuinlionx ret/nnliitij hiilnn Prosyectinii hr Oil m Tunntnki. 
In view of these conclusions, the writer recommends.- 

1. A thorough geological examination of the country to the cast and north-east of 
the subdivision, in the hope that payable oil-reservoirs may there be located nearer the 

2. A sysTi'nuirn prosjx'cting of the siiIkIi vision by means of deep bores at regular 
and considerable intervals. .Issuming the correctness of the depths recorded at the 
Carrington and Norfolk Road bores (24 and 23). no bore should be aliandoncd as 
"dry" unless it has reached a depth of 3,(H>0ft. below sea-level without obtaining 
oil. ' 

3. The systematic recording of the .strata passed thnnijjh in the bores, and the 
keeping of large and accurately labelled samples of these strata. 

4. The co-operation of all parties engaged in oil-prospecting, more esj)eciallv in 
regard to the comparison of strata passed through. The only way to insure compar- 
able results is to secure the constant presence on the field of a comi)etent geologist, 
who should examine and record all the specimens obtained. 

Although geological data are very meagre, the writer would recommend as the 
most likely zone for exploration by deep boring the strip of gas-producing country 
defined above. 

•For further particulars soc C.-'.t, Idlo. j). 2:{. 



(l.) IRONSAND.* 

( I . ) Inlrnductory. 
As stated in a previoTis chapter (pp. Ti . 28), the sand-dunes and beaches of the New 
Plymouth Subdivision are usually composed of black sand consisting largely of magnetite. 
The writer did not undertake any investigations into the relative amounts of magnetite 
and ferro-magnesian minerals occurring in this sand. The folloM'ing account of the 
composition and treatment of the sand is culled from a variety of sources. 

(2.) Composition of Ironsand. 
Many analyses of the Taranaki ironsand have been made from time to time. As 
would be expected, they show a very considerable range in composition, dependnig on the 
relative proportions of magnetite, ihnenite, ferro-magnesians, and other impurities in the 
samples.f The following analyses may be quoted as examples :— 

43 CO 












"a '^tc 





Ferric oxide 
Ferrous oxide 
Alumina . . 

Magnesia . . 
Phosphoric anhydride 
, (P2O5) 
Sulphuric anhydride 


Titanic anhydride 
Oxide of cob-ilt 
Sulphur . . 
Alkalie.s and mideter- 


40-68t i 
36-05J I 







9 •20 


e S 

^ « 00 






W 00 




29-60 1» 









- I 

<>. J. Siielus 
(Private Report) 


- -s s 

Metallic iron 58-7 \ 91-9|| 71-0^1 

Phosphorus ()-015 


7-500 6 


2 8-0 

It should be noted that Skey has shown that the ilmenito cannot be separated from the 
magnetite either by electro-magnetic or sifting processes (see Rep. Col. Lab., 1900, p. 17) 

o u * '^']<",!^"ter i.s much indobtod to Professor A. .larman. Director of the Auckland University Colleco 
t>chool of Mines, for advice ni regar.l to thi.s section, f A sample of ironsand from Patea recently analysed 
"u Z J^"™"'°" Laboratory was found to contain 0-lG per cent, of vanadium. If, as is therefore probable 
the Now I'lvraouth ironsand also contains some vanadium, and if this vanadium can be retained durine 
smelting and during the manufacture of steel, its value becomes considerable. t Equivalent to metallic 

iron _56-87 per cent. § Equivalent to metallic iron 60-3 per cent. i| Equivalent to metallic 

iron ;0- 1 per cent IJ Equivalent to metallic iron .>6- 1 i»r cent. ** Equivalent to phosphorus 00.3!) 

per cent. ff Equivalent to sulphur 0-004 per oont. 


(3.) tlistoiLi of Attempts fu final ihi- Iiotiaaml. 

The earliest attempt to smelt the Taranaki ironsand appears to have been made 
by a Mr. John Perry, a carpenter, who in 1848 erected a small furnace beside a 
tributary of the Huatoki River, near the Carrington Road, and succeeded in producing 
an inconsiderable quantity of iron, which was locally forged into small articles. In 
this, as in many subsequent attempts, the failure was chiefly due to the fineness of the sand. 

Shortly after this some unsuccessful experiments in the same direction were mado 
by Mr. C. Sutton. 

In 1858 a lease of ironsand was granted by the Provincial Government to Captain 
Morshead, who endeavoured, without success, to float a company in England to treat 
the ironsand. 

In 1869 Henochsburg and Co. erected a furnace on a site apparently quite close 
to that of the Bonithon Company's derrick (21 on map of Paritutu Survey District). 
Partial success attending this venture, the firm was extended into the Pioneer Steel 
Company, which, however, was apparently wound up or merged shortly after- 
wards into another, known as the New Zealand Titanic Steel and Iron Companv 
(Limited). This company was fonned chiefly by the exertions of Mr. E. M. Smith, 
the inventor of a method by which the ironsand was moulded with chiv into bricks, 
in order to prevent the choking of the furnaces. The smelting of the ironsand bv 
this method proved, it is said, a great success. The enterprise, nevertheless, cyllapsed 
for want of funds. After great exertions by Mr. Smith a company was floated in 
Wellington, wliich expended £20,U00 in the erection of up-to-date works near the 
mouth of the Henui River. After the completion of the works, however, only enough 
capital was left for the carrying-out of one trial smelting. On the 23rd September. 
1876, 3 tons 15 cwt. of pig iron was obtained. This was tested in England, and 
reported to be of the verj' best quality. After these experiments the furnace was 
blown out, and the works stood idle till 1884. when abortive attempts at smelting 
were successively made by Messrs. Hughes and Hipkins. In 1888 Messrs. (Jldlield and 
E. M. Smith made further trials, which, on the whole, appear to have been successful, 
but the operations terminated in 1889, when the Bank of New Zealand acquired the 
furnace and plant and removed them to Onehunga, near Auckland. 

In 1892 Mr. E. M. Smith obtained the sanction of the Bank of New Zealand to 
conduct further trials with the plant at Onehunga, the results of which a|)])ear to have 
been entirely satisfactory. Forty-five tons of iron were obtained, the iron running freelv, 
the tuyeres being clean, and only 2 to 3 per cent, of iron-oxide being left in the slag. 

In 1896 Mr. E. M. Smith visited England with samples of the steel manufai tured 
by himself from Taranaki ironsand. The prospects of the industry were most favourably 
reported on by various experts, including Mr. G. J. Snelus, F.R.S. Despite these 
favourable reports, however, Mr. Smith did not succeed in his efforts to float a company 
for the purpose of working the iron-deposits. 

During 1899 the New Zealand Government tried to arrange with the Esteve Steel 
Company to conduct experiments in improved methods of smelting the sand, but the 
parties were unable to come to terms. 

Mr. Smith revisited England in 1901 in company with Mr. (afterwards Six-) A. J. 
Cadman, and was again unsuccessful in raising capital for iron-works. Mr. Cadman, how- 
ever, returned to England in order to pursue the project. Since then another attempt 
to float a powerful company to develop the Parapara iron-ore* and the Taranaki ironsand 
has failed. 

It is said that at the present time a syndicate has undertaken to begin erecting 
plant for smelting the ironsand before April, 1912. 

• Regarding the potentialities of this deposit Fee Bulletin Xo. 'A, N.Z.<;.S. (New Series). 
4— New Plymouth. 


(4.) Method and Results of Smith's Patent Smelting Process. 

It may be of interest to give a short account of the process invented bv Mr. 
E. M. Smith for the smelting of the Taranakd ironsand. The method consisted in 
the manufacture of briquettes from ironsand and suitable fluxes, which were also 
used as the binding material. The mixture employed in the manufacture of the 
briquettes was as follows : Ironsand, 160 parts by weight ; " blue clay," 25 parts bv 
weight ; " yellow clay," 25 parts by weight. 

Various analyses of the ironsand are quot«d in a previous part of this section. 
The " blue " and the " yellow " clays were stated by Mr. Smith, in a paper read in 
1896 before the Iron and Steel Institute, to analyse as follows : — 









100-00 100-064 

In a private report* in 1896 Mr. G. .J. Snelus stated that he found the clavs to 

Blue Clav. 

YeUow Clav 















contain the following substances — 


Yellow Clay. 

10-580 ' 

Blue Clay. 

.. 5-440 
.. 1-879 
.. 0-049 
.. 1-870 

and therefore advised that the yellow clay, which was probably yellow tufa of the 
Pouakai Series of this bulletin, should be used in the manufacture of the briquettes rather 
than the blue clay, which was probably a claystone of the Onairo Series, since by 
this means the presence of an excess of sulphur and phosphorus in the pig iron would 
be avoided. The following are the results of analyses of pig iron and bar iron produced 
by Smith's process : — 

Pig Iron. 

Bar Iron. 

Smith (Paper read 
before Iron and 
Steel Institute). | 


Smith, lor. cil. 




Silicon . . 



Combined Carbon 


Loss and undetermined 
















' 0-850 
( 2-200 







*This report was published in the Xeu- Zealand Mines Record, vol. iv. 1900-1, pp. 47-49 See also 
vol. V, 1901-2, pp. 410-^17. 

t Apparently there is a small error in one of the percentages quoted, thus making the sum 0-005 too 
great. ■= ^ e 


The pig iron was described as a good grey, fairly granular, and extremely tough foundr)" 
iron, chilling with a clean surface. A fragment when struck on the an\'il was found 
to flatten out. Mr. Snelus remarks that it contains too much phosphorus and sulphur 
to be used in tlie acid Bessemer or Siemens processes, but considers that the greater 
part of these impurities comes from the blue clay used in the manufacture of the 
briquettes. The cjuality of the castings was most favourably reported on by experts. 
The bar iron was of excellent quahty, being very fine-grained and malleable. 

Mr. Smith akso foimd that, having smelted the ironsand contained in the briquettes, 
the liquid metal, if run into a ladle containing tarred ironsand in the proportion of 
4 cwt. to each ton of molten metal, would melt and absorl) the ironsand, resulting in 
a gain in weight of 3 cwt. per ton. The cost of the manufacture of pig iron superior 
in cpiality to the best Scotch was found to be £2 7s. 3d. per ton. In making wrought 
iron he found that tarred ironsand could be added in the puddling - furnace in the 
proportion of 50 per cent., and in the same proportion when making steel by the 
Siemens open-hearth funiace, resulting in an additional gain of 7 cwt. per ton. By 
this special treatment bar iron equal in quahty to best Barrow hferaatitc iron (B.B.H.) 
could be produced for £7 per ton. The manufactured wrought iron, when charcoal was 
used in the puddling-furnace, stood a tensile stress of 52 tons (?) to the square inch. 

The by-products obtained from the slag, in the form of bricks, slag cement, slag blocks, 
and ground slag to be used as a fertilizer, were all regarded as of considerable value. The 
fertilizer was estimated to have the following approximate composition : — 

Lime (soluble in acids) 4(»-0 

Alumina „ . . . . 12() 

Silica „ . . . . 420 

Magnesia . . . . 2-0 

Manganese .. Traces 

Titanium ,, 1-0 

Iron-oxide ,, 2-0 

Alkalies „ . . l-O 

(5.) Remarks on ihr Economic Possibilities oj the honsanrl. 

It will be noted that no mention is made of phosphorus in the analysis quoted 
above, yet it is on account of its phosphate-content that basic slag is employed as 
H fertilizer. Slag blocks though durable, are usually too slippery for paving-blocks, and 
are at present not likely to find any market in the neighbourhood of the proposed iron- 
works. Slag cement is. at the best, far from equal to Portland cement, and could hardly 
be expected to find a ready sale in New Zealand, where very good cement can be 
cheaply made. 

It appears, therefore, that the by-products referred to above should not be counted 
on in arriving at conclusions as to the economic possibilities of the ironsand. 

Some doubt must also be expressed as to wlicther the samples of ironsand, analyses 
of which are quoted above, were true average samples. In some places, as, for example, in 
the neighbourhood of Paritutu. owing probably to the prevailing tidal currents, there 
appear to be very large accumulations of almost pure magnetic ironsand. Along the open 
beaches, however, and on the sand-dunes, the heavier magnetite and ilnienite grains are 
frequently sorted out by the action of wind and waves, and form a thin covering to a 
more heterogeneous sand. It would therefore be advisable, before any erection of smelting- 
works is undertaken, to carry out a very thorough and exhaustive sampling of the ironsand 
deposits of the subdivision. In this sampling mere surface material should not be allowed 
to predominate unduly, but the character of the sand from various depths in the deposits 
should be fully taken into account. 
5 — New Pljmoatb. 



Deposits of bog iron-ore are found in places in the western portion of the New 
Plynioiith Subdivision, in the area occupied t)y the Pouakai 8eries, from the iron- 
bearing minerals of which the ore has been derived. They are most noticeable near 
Urenui, in the coimtry in the neighbourhood of the southern part of Smart Road, and 
in the low country to the west of Burton's Hill. The deposits apparently are never 
inore than 2 ft. or 3 ft. in thickness, and occur only in small patches. From an 
economic standpoint, therefore, the limonite-deposits do not call for further notirp. 

Materials for .Roadmaking. 

In the western portion of the subdivision abimdant road-metal is obtained by 
breaking the volcanic boulders, which are either quarried, more especiallj' in the small 
liills near Lepperton, or are carted from the beds of streams or from the boulder- 
strewn portions of the sea-front. 

In the greater part of the Waitara Survey District, where the volcanic rocks 
are poorly developed or absent, considerable difficulty is experienced in obtaining 
satisfactory road-metal. The quartzose conglomerate furnishes a material which is 
excellent, except that the extreme hardness of the pebbles causes rapid wearing-out of 
horse-shoes. The calcareous concretions which are frequently abundant in the Onairo 
rocks make a good road-metal, more especially where they contain abundant fossils. 

Building and Pottery Materials. 

The volcanic rocks of the Pouakai Series would form a good building-material were 
it not that the labour of trimming is so considerable. 

Near Waitara a claystone of the Onairo Series, and near New Plymouth a fine 
tufa of the Pouakai Series, have for many^ years furnished rav; material for brick-making. 

On the Smart Road considerable deposits of exceedingly decomposed and bleached 
volcanic rock occur. Similar deposits are also to be found near the upper waters of 
the Huatokd Stream, whence they extend at intervals towards the base of the Pouakai 

The clay from Smart Road is said to have been tested by experts, and reported 
upon very favourably, as a material for the manufacture of the finer kinds of pottery. 
Analyses of this clay are as follows : — 

Silica (SiOj) . . 

Alumina (AUO3) 

Ferric oxide (FcgO,) 

Lime (CaO) . . 

Magnesia (MgO) 

Potash (K2O) . . 

Soda (Na^O) . . 

Titanium-dioxide (TiOg) 

Carbonic anhydride (CO^) 

Moisture lost at 100° C. . . 

Combined water and organic matter 



























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i M D E X 

Acknowledgments, 3. 

Adniu-alty, British, oil piesenieii to, 36. 

.^olian deposits, 28. (See aUo Sand-dunes.) 

Agglomerates, volcanic, 1.5, 21. 22. 24. 20. (See 

aldo Pouakai Series.) 
Agriculture, dairying, &c., 1, .'!. 
Alluvial deposit.s, 12, 2G-27. 

Alpha or " Oil or London " Well, 30, o3. (See 
also Tabular comparison of records of bores, in 
tnap- pocket.) 
Analyses of clay and claystones, 16, 17. .50. 

„ infusorial earth, 27. 

„ iron, 50. 

„ ironsand, 48. 

„ peat, 27. 

„ petroleum, 41-42. 

,, salt water. 40 

3lag, 51. 

volcanic rocks, 23. 24. 
Andesites, 22, 23, 24. 

Anticlinal theory of oil-accumulation, 17, 38. 
Anticlines, 17, 18, 38, 47. 
Anticlinorium, 18, 38. 
Area of subdivision, 2. 
Artesian wells, 15, 45. 
Awakino district, geology of, &c., 19. 


Balehitha Water-gas Company buys cru<le oil, 32. 

Balloch, \V., oil-ilriller. 3, 6. " 

Bell, J. M., 11. 43. 

Benzene, 43. 

Berry. W., improves yield from oil-well, 34. 

Beta" or " Uil or Ediriburgh " Well, 31. 53. 

Birthday Well, 33, 34, 53. 

Bishop, — , gas-escape on farm of, 24, 44. 

Bog iron-ore, 20, 27, 52. 

Bonithon Freehold Petroleum Comiiany, 30-37. 

Bonithon Freehold Petroleum Extended Company, 

Booth. —, oil driller. 31. 
Booth's well, 31, 32, .53. 

Boreholes, bore-sites, &c., 2, !l. 10. 11, 1.5, 29 el set/. 
crowding of, 37. 
„ inaccurate logs of. 37. 

„ insutticient depths of, 35, 36, 37. 

(See itUo Tabular comjiarison, »« nmp-pocket.) 
Boundaries of subdivision, 2. 

Breakwater, Xew Plymouth, bores near. 2, 10, 29 «< 

se(j., 53. 
>• „ oil-seepages near, 30, 

Breccias, volcanic. 15. 21. 22, 24, 25, 26. (6'ee also 

Pouakai Series.) 
Brickmaking, 2. 52. 
Brine, 34, 40. 
Briquettes, ironsand, 50. 
Building-materials, 52. 
Bunger, H. E., oil-driller, 37. 

Cadman, Sir A. J., associated with Taranaki iron- 
sand, Ac, 49. 
Carbon-dio.xide in gas from oil-bores, 40. 
Carboniferous (Maitai) rocks, supposed, 17. 
Carter and others, oil lease held by, 30, 33. 
Clarke, E. de C, 11. 
Classification, geological, table of, 14. 
Clays, 17, 50, 52. 

analyses of, 17, 50, 52. 
Claystone, 12, 1.5, 1(>-17, 19. 
analyses of, 16, 17. 

masses of. in volcanic agglomerate, 15, 
16, 24, 25. 
„ reddened and baked by volcanic action, 

21, 24. 
Cliffs, 4, 6, 7, 15, &c. 
Coal, 1, 9, 16, 19. 
Coast-line, 5, 6, 7, 21, &c. 
Coastal plain, 5-6. 
Communication, means of, 4. 
Comparison of records of bores, tabular, in iii<ifj- 

Conclusions re petroleum, 46-47. 
Concretions, calcareous, 12, 16, .52. 
Conglomerate of Miocene rocks, 8, 12, 17, 18. 

Pouakai Series, 8, 21, 22, 24, 52. 
Conical hills near Lepperton and Inglewood. 5. 21. 

Copper-ore, 10. 

Corkill, F. P., documents lent by, 30. 
Craig and Co., A. F., report on Taranaki oil by 

42, 43. 
Creta ceo -tertiary rocks, supposed, 18, 19. 
Current bedding, 21. 

Dairying, 1,3. 

Davies, R. \V., 2, 39. 

Davies, W., reported gas-escape on farm of, 44. 

Debris, volcanic, 5, 7, 8, 15, 16, 21 et seq. (Set 

also Pouakai Series ; Egmont, Mount.) 
Denudation, 6, 7, 8, 26, 27. 
„ marine, 6, 7, 8. 

Depression of land, 7, 18, 26. 
Dieffenbach, E., 9, 30. 
Drainage-svstem, drainage-channels, 4, 6. 
Dunes, sand. 0, 7, 12. 28. 48. 


Egmont. Mount, 3, 4, 8, 22, 20. 

„ „ andesitic rocks of, 26. 

,, ,, eruptions of, 8, 26. 

Egmont Petroleum and Mineral Boring Company. 

Elevation of land, 4, 7. 
Eocene strata, supposed, 18. 
Erosion (see Denudation). 



Fair, ti. C, oil-driller, 33, 34. 

Fair, Mrs. G. C, documents lent bv, 30. 

Fair, R. E., oil-driller, 32. 

Faulting, 7, 8, 12, 18. 

Flood-plains, 6. 

" Forest, buried," 12, 24. 

Fossils, 12, 15, 16, 17, 19, 20, 25. 

„ supposed Triassic, 19. 
Freezing- works at Waitara, 3, 15, 45. 
Freshwater strata, 24 (?), 26-27. 


Gas, natural, analyses of, 46. 

,, met with in oU-bores, 31 et seq. 

,, used for steam -raising, 35, 43. 

„ explosions and fires, 32, 33, 35, 45. 

,, vents and escapes, 24, 27, 36, 43-45, 47. 

„ bearing strata, 47, &c. 
Geological classification, table of, 14. 
history, 8, 13. 
,, work, conduct and character of, 2. 

,, „ economic reasons for, 2. 

Geology, economic, 29-52. (See also Appendix, 

and Tabular comparison of bore.s, in mnp-pocket. ) 
Geologj', general, 12-28. 
German HUl, springs at, 7. 
Gold, prospecting for, 2. 
Gorges, 6. 
Gravels, 21, 22, 26. 
Grooby, — , gas-escapes on farm of, 27, 44. 

H. ■ 

Harbours, 4. 

Hector, James, 9, 11, 14, 15, 18, 19, 30. 

Henochsburg and Co., ironsand-smelting by, 49. 

Henry, J. D., 35. 

Henui River, ironworks near, 49. 

Hicks and Vickery, discovery of traces of oil by, 39. 

Hill, Henry, 10. 

Hills, ridges, &c., 5. 

History, early, 4. 

,, geological, 8, 13. 
Huatold River, gas-escapes on or near. 43-44 
Button. F. W.. 10, 20, 22, 23. 


Igneous rocks, 5, 9, 10, 22-24. {See ahn Pnnakai 

Series. ) 
Ilmenite m ironsand, 27. 48. 51. 
Industries, 3. 

Information, general, 1-11. 
Infusorial earth. 27. 

„ analysis of, 27. 

Inglewood, boring for oil near, 29, 3(i. 
,, conical hiUs near, 5, 21, 24. 

,, gas-escape near, 44. 

,, Oil-boring and Prospecting Compan}-, 

„ [Oil] Company, 29. 

Inorganic theory of oil-formation. 37. 
Iron, 2, 10, 48-52. 
,, analj'ses of, 50. 

cost of manufacture of, 51. 
,, manufacture of. from ironsand, 2, 10, 49 et 

„ ore.s, 26, 48-52. {See also Ironsand, &c.) 

Iron-oxide, deposited by springe, 7. 
,, (liinonite), 62. 

(magnetite), {see Ironsand). 
Iron, properties of, 10, 51. 

,, slag, composition of, 51. 
Ironsand, 2, 10, 26, 27, 28. 48-51. 
„ analyses of, 48. 

„ economic possibihties of, 51. 

,, sampUng of, 51. 

smelting of, 2, 10, 49, 50-51. 
Islands, islets, 4. 5, &c. {See aho Sugar-loaves.) 

Jarman. A., 48 (footnote). 


Kaitaki or Patua Range. 10, 26. 

Kaolin, impure, 52. 

Keith, L., oil-driller, 34. 

Kerosene, 43. 

Kotuku, analysis of oil from, 41. 

Lacustrine deposits, 26. {See also Swamp deposits. ) 

Lagoon near Paritutu, 6. 

Lands and Survey Office, New Plymouth. 2. 3. 

Lepperton, conical hills near, 5, 21, 24. 

Lignite, buried wood, &c., 12. 21, 24. 

Limestone, 15. 16, 19. 

Limonite, 52. (5ee nZ«o Bog iron-ore.) 

Literature, list of, 9-11. 

Ludlow, — , oil-driller, 32. 


Macadamizing roads, 2, 52. 
McCoU, P., boring by, 33, 53. 
McDonald, A. D., oil-driller, 35, 36. 
Mace's or Herekawe bore, 32, 53, 
McKay, Alexander, 10, 11, 19. 
Maclaurin, J. S., 3, 10, 27, 40. 
Magnetite, 27, 48, 51. {See also Ironsand.) 
Maitai Series, rocks referred to, 17. 
Manganiauhcte Stream, gas-escape near. 44. 
Manganui River, 8. 

,, oil-bores near, 31. 

Mangaone Stream, gas-pscape near. 44. 
Mantdl, G. A., 9. " 

Manukau Heads, volcanic breccias of. 25, 26. 
Marine and fluvio-marine deposits ((Junternarv). 27. 

{See aho Ironsand.) 
Marine denudation, 6, 7. S. 
Marshall, P., 10, 26. 
Marvin, Charles, oil-expert, 31. 
Mary viUe Coal-mine (Mokau). IS. 
Mikotahi (Sugar-loaf), 5, 22. 
-Vlioceue strata, 12, 15, 21 . {Set- alio Oiinii o Serirs ; 

Pouakai Series.) 
Moa Bore. 36, 40, .53. 

Moa Petroleum (Limited) (oil company), 36. 
Mokau district, coal and geology of. 1. 18, 19. 
Mokau River, course of, 8. 

„ coal-mining on, I . 

Moishead, Captain, iron.sand lease held hv. 49. 
Mot'.iroa (Sugai-loaf), 5. 

,, oil near, 30. {See alio Petroleuiu.) 

,, Petroleum Company, 34. 
'■ Mud volcano," 45. 


New Plyraouth, town and harbour of, 4. 
[Oil] Company, 10. 
„ Oil and Freehold Company, 39. 

Petroleum Company, 37. 
,, subdivision, boundaries of, 2. 

Nf« Zealand Petroleum and Iron Syndicate, 31. 
Standard Oil Company, 29, 3(3. 
., Titanic Iron and Steel Company, Ut. 

North Auc-ivland, Miocene volcanic rocks of. 22, 23, 
25, 2»>. 


Oamaru (AlioceueJ age, roclv.s of, 21. (.Set nUo 

Onairo Series). 
Okey's l)ore, 33, 53. 
Oil (petroleum), 2, 0, 10, 11, 29-17, 53. 
,, analyses and composition of, 9, 10, 40—43. 
,, boring for, 2, 9, 10, 1 1, 29 el neq., 53. 
„ evidences of, 38 et acq. 
,, horizons, 11, 47. 
,, mode of accumulation of, 38. 
„ physical properties of, 40. 
,, prospecting; for, 37, 47. 
„ seepages, 30, 39-40, 47. 
,. source of, 9, 10, 37-38, 40, 47. 
„ wells, 10, 29 et stt/., 53. 
•' OU or Dublin "' Well, 31, .03. 
•' Oil or Edinburf^h ' Well, 31, 53. 
" Oil or London '" Well, 30, 53. 

{See also Petroleum, and Tabulated comjjari- 
son of bores, in ntap- pocket.) 
Onairo Series, 5, ti, 12, 1.5-21, 38. 

,, age and correlation of, 12, 15, 21. 

„ clavstones and sandstones of, 12, 15, 

iVn, 24. 
,, conglomerates of, 12, 17, Its. 

,. distribution of, 15-10. 

interrelation.ship of members of, 

paheontology of, 19-20. 
petrology of, 16-17. 
relationship to Pouakai Series of, 25. 
structure of, 12, 17-18, 38. 
Onehunga, iron-smelting at, 49. 
Organic theory of oil -formation, 38. 

Petroleum, jirospecting for, 37, 47. 
„ seepages of, 30, 39-40, 47. 

,, shipments of. 32, 35. 

source of, 9, 10, 37-38. 
trials of, for various purposes, 32, 35, 43. 
wells, 10, 29 et seq., 53. 
(6'cc al^o Tabulated comparison of bores, in 
map-pocket. ) 
Petrology of Onairo Series, l(j-17. 

,, Pouakai Series, 22-24. 

Physiography, 4-8. 
Pioneer Steel Company, 49. 
Plain, coastal, .5-6. 
Plains, 5, 6. 

flood, 6. 
Plant-remains, 12, 24, 25. 
Pleistocene deposits, 12, 26-28. 
Ponds, 6-7. 
Population, 4. 
Pottery materials, 52. 
Pouakai Range, 8, 24, &c. 

,, rocks of {see Pouakai Series). 

Pouakai Series, 5, 6, 12, 21-26, 38. 

,, age and correlation of, 25-26. 

,, agglomerates and breccias of. 15. 

21, 22, 25. 
,, analyses of rocks of, 23, 24. 

,, claystones associated with, 15, 24, 

„ conglomerates of, 21, 2^, 52. 

,, distribution of, 15, 16, 21. 

,, flow-rocks (lavas) of, 21. 

,. interrelationship of members of, 

lignite and buried wood of, 12, 21 

origin of, 24-25. 
petrology of, 22-24. 
relationship to Onairo Series of, 25. 
structure of, 21-22, 38. 
thickness of, 21. 
Prospecting, systematic, recommended. 47. 
Putt's bore. 33, .53. 
Pvrite, 16. 


(^uartzose conglomerate (Pouakai Series), 21, 22, 

Quaternary strata, 12, 26-28. 


Palaeontology of Onairo Series, 19-20. (See uUo 

Paraffin in petroleum, 41, 42, 43. 
Parapara iron-ore, 49. 
Paritutu (Sugar-loaf), 4, 21, 25. 
Park. James, 9, 11, 14, 15, 19, 20. 
Patua or Kaitaki Range, metalliferous rocks of, 10. 

,, volcanic rocks of, 26. 

Peat and pieaty deposits, 26, 27, 45. 

,, analyses of, 27. 
People's Petroleum Company, 31. 
Perry. John, iron-smelting by, 49. 
Petch, A. S., gas-escape on farm of, 43. 
Petroleum, 2, 9, 10, 11, 29-47, .53. 

analy-ses and composition of, 9, 10, 40- 

boring for, 2, 9. 10, 11, 29 e< seq., 53. 

evidences of, 38 et seq. 

horizons, 11. 

industry, present position of, 29. 
„ .. history of, 30-37. 

mode of accumulation of, 38. 


Railway Department buys crude oil, 32, 35. 

,, , locopiotive trials bv, 43. 

Rainfall, 3. 
Recent and Pleistocene deposits, 12, 2t)-28. (See 

also Alluvial deposits.) 
Recommendations re pro.specting, 47. 
Redwood. Boverton, 42, 43. 
Reefs (sea-coast), 5, 30. 
River-flats, 6. 
Rivers, 6, 7, 8. 

ancient of, &c., 8. 

partly engulfed by .sea, 6, 7. 
Roadmaking, materials for, .52. 
Rotokare or Ratapihipihi Lagoon, 7, 18. 
Roy's well, 34, 53. 


Sagging of strata, 16-17. 
Salt water in oil-well.s, 34, 40. 
analysis of, 40. 



Samuel, Hon. Oliver, oil-boring by, 31, 32, 33. 

Samuel Syndicates, 10, 32, 33. 

Samucl'.s bore, 32, 53. 

Sand-dunes, .sandliilLs, .5, (i, 7, 12, 28, 48. 

Sands, 2G, 27, 28. (Scf alio Sand-dunes ; Iron- 

Sandstones, 10, 19. 

Scenery, 3-4. 

Sea encroaching on land, (J, 7, 8. 
,, oil floating on surface of, 39. 

Segregations or concretion.s, calcareou.s, 12, Ifi, .52. 

Silver in rock.s of Patua Range, 10. 

Sinijjson, Frank, 3. 

Simpson, W. A., oil-driller, 34. 

Sinter, calcareous, 7. 
,, [siliceous], 10. 

Skerries, 4. 

Skev. William, 9, 42, 51. 

Skinner, W. H., 3. 

Smith, E. M., 10, 17, 30, 49, 50, 51. 

,, iron-smelting by, 10, 17, 50-51. 

Snelus, (}. J., report on iron industry by, 49, 51. 

„ analyses by, 50. 

Springs, 7. 

Standard Oil Company of New Zealand, 29, 3(5. 
Stone, building, 52. 
" Streaks, hard," 10. 
Structure of geological formations, 12, 13, 17-18. 

21-22, 38. 
Subsidence, local, areas of, 7, 18. 
Sugar-loaves, New Plymouth, 4, 5, 21, 22, 25, &c. 

(See also Paritutu ; Mikotahi ; Moturoa.) 
Sunken river-mouths, 7. 
Sutton, C, smelting of iron.sand by. 49. 
Swamp deposits, 26, 27. 
Swamps, 6. 
Synclines, 17, 18, 47. 


Table of geological classification, 14. 

„ oil-wells, 53. 
Tables of rainfall and temperature, 3. 
Tabular comparison of records of bores, in map 

Tapuae-Manganui Ridge, 5, 8. 

„ origin of, 8. 

Taranaki, settlement of, 4. 

,, Divi-sion and Land District, 1. 

,, ironsand (see Ironsand). 

., on and Freehold Company. 29, 36. 

Petroleum Company (1860), 30, 31. 
.. „ (present). 29. 34-35. 

Temperature, monthly, 3. 
Terraces, 5, 6. 
Tertiary formations, N.Z;, summary of, 20. 

„ rocks (see Onairo Series ; Pouakai Series). 
Tongaporutu, geology of, &c., 19. 

Topography (set Physiography). 

Towns, 4. 

Trachyte of Sugar-loaves, supposed, 22, 23. 

Trees, carbonized stumps of, 25. 

Tria.ssie rocks, probable (near Awakino), 19. 


Unconformities, real or supposed, 15, 18, 19, 25. 

26, 28. 
Urcnui, analy.sis of clay from. 17. 

fossils near, 19. 

lignite near, 24. 

limonite (bog iron-ore) near. 52. 

Vanadium in iron.sand, 4S (footnote). 
Veale's bore, 33, 53. 

Vickery and Hicks, traces of oil reported bv. 39. 
Victoria or " Oil or Dublin " Well. 31. 
Volcanic action, 8, 12, 21, 24, 46. 
,, i-ocks, 5, 9, 10, 12, 21 ct seq. 

(See also Pouakai Series ; Sugar-loaves ; Eg- 
mont (Mount), &c. 
\'olcano in Pouakai times near Jlangaone Stream, 

supposed, 24. 
Volcano or volcanoes, ancient, of Pouakai Range. 

. 24. 
■' Volcano, mud," near Manganui River, 45. 


Waitangi Hill (Gisborne district), analysis of oil 

from, 41. 
Waitara, town and harbour of, 4. 
River, 4, 6, 8. 
,, oil on sea near, 39. 
Waitemata beds, 25. 

Wanner, Dr. J. (Bonn University), 21, 24. 
Water in bores rises and falls witli tides, 32. 
Water, salt, 34. 40. 
Waterfalls, 6. 
Watkins, A. E., 3, 39. 
Wells, artesian, 15, 45. 

„ oil (see Oil ; Petroleum). 
Weston, Henry, indications of oil on farm of, 39. 
Whangaroa Subdivision, andesites of, 22. 
White Cliffs, geology of. *c., 4, 18, 19. 

Zinc-blende in " ironsand." 27. 

By Authority : John Mackay, Government Printer, Wellington.~1912. 


5 1 G J 


University of